smmap2-2.0.1/0000755000076600000240000000000013002673663013174 5ustar byronstaff00000000000000smmap2-2.0.1/PKG-INFO0000644000076600000240000001255713002673663014303 0ustar byronstaff00000000000000Metadata-Version: 1.1 Name: smmap2 Version: 2.0.1 Summary: A pure python implementation of a sliding window memory map manager Home-page: https://github.com/Byron/smmap Author: Sebastian Thiel Author-email: byronimo@gmail.com License: BSD Description: ## Motivation When reading from many possibly large files in a fashion similar to random access, it is usually the fastest and most efficient to use memory maps. Although memory maps have many advantages, they represent a very limited system resource as every map uses one file descriptor, whose amount is limited per process. On 32 bit systems, the amount of memory you can have mapped at a time is naturally limited to theoretical 4GB of memory, which may not be enough for some applications. ## Overview [![Build Status](https://travis-ci.org/gitpython-developers/smmap.svg?branch=master)](https://travis-ci.org/gitpython-developers/smmap) [![Build status](https://ci.appveyor.com/api/projects/status/kuws846av5lvmugo?svg=true&passingText=windows%20OK&failingText=windows%20failed)](https://ci.appveyor.com/project/Byron/smmap) [![Coverage Status](https://coveralls.io/repos/gitpython-developers/smmap/badge.png)](https://coveralls.io/r/gitpython-developers/smmap) [![Issue Stats](http://www.issuestats.com/github/gitpython-developers/smmap/badge/pr)](http://www.issuestats.com/github/gitpython-developers/smmap) [![Issue Stats](http://www.issuestats.com/github/gitpython-developers/smmap/badge/issue)](http://www.issuestats.com/github/gitpython-developers/smmap) Smmap wraps an interface around mmap and tracks the mapped files as well as the amount of clients who use it. If the system runs out of resources, or if a memory limit is reached, it will automatically unload unused maps to allow continued operation. To allow processing large files even on 32 bit systems, it allows only portions of the file to be mapped. Once the user reads beyond the mapped region, smmap will automatically map the next required region, unloading unused regions using a LRU algorithm. The interface also works around the missing offset parameter in python implementations up to python 2.5. Although the library can be used most efficiently with its native interface, a Buffer implementation is provided to hide these details behind a simple string-like interface. For performance critical 64 bit applications, a simplified version of memory mapping is provided which always maps the whole file, but still provides the benefit of unloading unused mappings on demand. ## Prerequisites * Python 2.4, 2.5, 2.6, 2.7 or 3.3 * OSX, Windows or Linux The package was tested on all of the previously mentioned configurations. ## Limitations * The memory access is read-only by design. * In python below 2.6, memory maps will be created in compatibility mode which works, but creates inefficient memory mappings as they always start at offset 0. ## Installing smmap [![Documentation Status](https://readthedocs.org/projects/smmap/badge/?version=latest)](https://readthedocs.org/projects/smmap/?badge=latest) Its easiest to install smmap using the [pip](http://www.pip-installer.org/en/latest) program: ```bash $ pip install smmap ``` As the command will install smmap in your respective python distribution, you will most likely need root permissions to authorize the required changes. If you have downloaded the source archive, the package can be installed by running the `setup.py` script: ```bash $ python setup.py install ``` It is advised to have a look at the **Usage Guide** for a brief introduction on the different database implementations. ## Homepage and Links The project is home on github at https://github.com/gitpython-developers/smmap . The latest source can be cloned from github as well: * git://github.com/gitpython-developers/smmap.git For support, please use the git-python mailing list: * http://groups.google.com/group/git-python Issues can be filed on github: * https://github.com/gitpython-developers/smmap/issues ## License Information *smmap* is licensed under the New BSD License. Platform: any Classifier: Development Status :: 5 - Production/Stable Classifier: Environment :: Console Classifier: Intended Audience :: Developers Classifier: License :: OSI Approved :: BSD License Classifier: Operating System :: OS Independent Classifier: Operating System :: POSIX Classifier: Operating System :: Microsoft :: Windows Classifier: Operating System :: MacOS :: MacOS X Classifier: Programming Language :: Python Classifier: Programming Language :: Python :: 2 Classifier: Programming Language :: Python :: 2.6 Classifier: Programming Language :: Python :: 2.7 Classifier: Programming Language :: Python :: 3 Classifier: Programming Language :: Python :: 3.3 Classifier: Programming Language :: Python :: 3.4 smmap2-2.0.1/setup.cfg0000644000076600000240000000020613002673663015013 0ustar byronstaff00000000000000[bdist_wheel] universal = 1 [flake8] exclude = .tox,.venv,build,dist,doc [egg_info] tag_build = tag_date = 0 tag_svn_revision = 0 smmap2-2.0.1/setup.py0000755000076600000240000000364113000650747014711 0ustar byronstaff00000000000000#!/usr/bin/env python import os import codecs try: from setuptools import setup, find_packages except ImportError: from ez_setup import use_setuptools use_setuptools() from setuptools import setup, find_packages import smmap if os.path.exists("README.md"): long_description = codecs.open('README.md', "r", "utf-8").read() else: long_description = "See http://github.com/gitpython-developers/smmap" setup( name="smmap2", version=smmap.__version__, description="A pure python implementation of a sliding window memory map manager", author=smmap.__author__, author_email=smmap.__contact__, url=smmap.__homepage__, platforms=["any"], license="BSD", packages=find_packages(), zip_safe=True, classifiers=[ # Picked from # http://pypi.python.org/pypi?:action=list_classifiers #"Development Status :: 1 - Planning", #"Development Status :: 2 - Pre-Alpha", #"Development Status :: 3 - Alpha", # "Development Status :: 4 - Beta", "Development Status :: 5 - Production/Stable", #"Development Status :: 6 - Mature", #"Development Status :: 7 - Inactive", "Environment :: Console", "Intended Audience :: Developers", "License :: OSI Approved :: BSD License", "Operating System :: OS Independent", "Operating System :: POSIX", "Operating System :: Microsoft :: Windows", "Operating System :: MacOS :: MacOS X", "Programming Language :: Python", "Programming Language :: Python :: 2", "Programming Language :: Python :: 2.6", "Programming Language :: Python :: 2.7", "Programming Language :: Python :: 3", "Programming Language :: Python :: 3.3", "Programming Language :: Python :: 3.4", ], long_description=long_description, tests_require=('nose', 'nosexcover'), test_suite='nose.collector' ) smmap2-2.0.1/smmap/0000755000076600000240000000000013002673663014311 5ustar byronstaff00000000000000smmap2-2.0.1/smmap/__init__.py0000644000076600000240000000050713002673557016426 0ustar byronstaff00000000000000"""Intialize the smmap package""" __author__ = "Sebastian Thiel" __contact__ = "byronimo@gmail.com" __homepage__ = "https://github.com/Byron/smmap" version_info = (2, 0, 1) __version__ = '.'.join(str(i) for i in version_info) # make everything available in root package for convenience from .mman import * from .buf import * smmap2-2.0.1/smmap/buf.py0000644000076600000240000001456412776377451015466 0ustar byronstaff00000000000000"""Module with a simple buffer implementation using the memory manager""" import sys __all__ = ["SlidingWindowMapBuffer"] import sys try: bytes except NameError: bytes = str class SlidingWindowMapBuffer(object): """A buffer like object which allows direct byte-wise object and slicing into memory of a mapped file. The mapping is controlled by the provided cursor. The buffer is relative, that is if you map an offset, index 0 will map to the first byte at the offset you used during initialization or begin_access **Note:** Although this type effectively hides the fact that there are mapped windows underneath, it can unfortunately not be used in any non-pure python method which needs a buffer or string""" __slots__ = ( '_c', # our cursor '_size', # our supposed size ) def __init__(self, cursor=None, offset=0, size=sys.maxsize, flags=0): """Initalize the instance to operate on the given cursor. :param cursor: if not None, the associated cursor to the file you want to access If None, you have call begin_access before using the buffer and provide a cursor :param offset: absolute offset in bytes :param size: the total size of the mapping. Defaults to the maximum possible size From that point on, the __len__ of the buffer will be the given size or the file size. If the size is larger than the mappable area, you can only access the actually available area, although the length of the buffer is reported to be your given size. Hence it is in your own interest to provide a proper size ! :param flags: Additional flags to be passed to os.open :raise ValueError: if the buffer could not achieve a valid state""" self._c = cursor if cursor and not self.begin_access(cursor, offset, size, flags): raise ValueError("Failed to allocate the buffer - probably the given offset is out of bounds") # END handle offset def __del__(self): self.end_access() def __enter__(self): return self def __exit__(self, exc_type, exc_value, traceback): self.end_access() def __len__(self): return self._size def __getitem__(self, i): if isinstance(i, slice): return self.__getslice__(i.start or 0, i.stop or self._size) c = self._c assert c.is_valid() if i < 0: i = self._size + i if not c.includes_ofs(i): c.use_region(i, 1) # END handle region usage return c.buffer()[i - c.ofs_begin()] def __getslice__(self, i, j): c = self._c # fast path, slice fully included - safes a concatenate operation and # should be the default assert c.is_valid() if i < 0: i = self._size + i if j == sys.maxsize: j = self._size if j < 0: j = self._size + j if (c.ofs_begin() <= i) and (j < c.ofs_end()): b = c.ofs_begin() return c.buffer()[i - b:j - b] else: l = j - i # total length ofs = i # It's fastest to keep tokens and join later, especially in py3, which was 7 times slower # in the previous iteration of this code pyvers = sys.version_info[:2] if (3, 0) <= pyvers <= (3, 3): # Memory view cannot be joined below python 3.4 ... out = bytes() while l: c.use_region(ofs, l) assert c.is_valid() d = c.buffer()[:l] ofs += len(d) l -= len(d) # This is slower than the join ... but what can we do ... out += d del(d) # END while there are bytes to read return out else: md = list() while l: c.use_region(ofs, l) assert c.is_valid() d = c.buffer()[:l] ofs += len(d) l -= len(d) # Make sure we don't keep references, as c.use_region() might attempt to free resources, but # can't unless we use pure bytes if hasattr(d, 'tobytes'): d = d.tobytes() md.append(d) # END while there are bytes to read return bytes().join(md) # END fast or slow path #{ Interface def begin_access(self, cursor=None, offset=0, size=sys.maxsize, flags=0): """Call this before the first use of this instance. The method was already called by the constructor in case sufficient information was provided. For more information no the parameters, see the __init__ method :param path: if cursor is None the existing one will be used. :return: True if the buffer can be used""" if cursor: self._c = cursor # END update our cursor # reuse existing cursors if possible if self._c is not None and self._c.is_associated(): res = self._c.use_region(offset, size, flags).is_valid() if res: # if given size is too large or default, we computer a proper size # If its smaller, we assume the combination between offset and size # as chosen by the user is correct and use it ! # If not, the user is in trouble. if size > self._c.file_size(): size = self._c.file_size() - offset # END handle size self._size = size # END set size return res # END use our cursor return False def end_access(self): """Call this method once you are done using the instance. It is automatically called on destruction, and should be called just in time to allow system resources to be freed. Once you called end_access, you must call begin access before reusing this instance!""" self._size = 0 if self._c is not None: self._c.unuse_region() # END unuse region def cursor(self): """:return: the currently set cursor which provides access to the data""" return self._c #}END interface smmap2-2.0.1/smmap/exc.py0000644000076600000240000000045212637461251015444 0ustar byronstaff00000000000000"""Module with system exceptions""" class MemoryManagerError(Exception): """Base class for all exceptions thrown by the memory manager""" class RegionCollectionError(MemoryManagerError): """Thrown if a memory region could not be collected, or if no region for collection was found""" smmap2-2.0.1/smmap/mman.py0000644000076600000240000005703613002673431015617 0ustar byronstaff00000000000000"""Module containing a memory memory manager which provides a sliding window on a number of memory mapped files""" from .util import ( MapWindow, MapRegion, MapRegionList, is_64_bit, string_types, buffer, ) import sys from functools import reduce __all__ = ["StaticWindowMapManager", "SlidingWindowMapManager", "WindowCursor"] #{ Utilities #}END utilities class WindowCursor(object): """ Pointer into the mapped region of the memory manager, keeping the map alive until it is destroyed and no other client uses it. Cursors should not be created manually, but are instead returned by the SlidingWindowMapManager **Note:**: The current implementation is suited for static and sliding window managers, but it also means that it must be suited for the somewhat quite different sliding manager. It could be improved, but I see no real need to do so.""" __slots__ = ( '_manager', # the manger keeping all file regions '_rlist', # a regions list with regions for our file '_region', # our current class:`MapRegion` or None '_ofs', # relative offset from the actually mapped area to our start area '_size' # maximum size we should provide ) def __init__(self, manager=None, regions=None): self._manager = manager self._rlist = regions self._region = None self._ofs = 0 self._size = 0 def __del__(self): self._destroy() def __enter__(self): return self def __exit__(self, exc_type, exc_value, traceback): self._destroy() def _destroy(self): """Destruction code to decrement counters""" self.unuse_region() if self._rlist is not None: # Actual client count, which doesn't include the reference kept by the manager, nor ours # as we are about to be deleted try: if len(self._rlist) == 0: # Free all resources associated with the mapped file self._manager._fdict.pop(self._rlist.path_or_fd()) # END remove regions list from manager except (TypeError, KeyError): # sometimes, during shutdown, getrefcount is None. Its possible # to re-import it, however, its probably better to just ignore # this python problem (for now). # The next step is to get rid of the error prone getrefcount alltogether. pass # END exception handling # END handle regions def _copy_from(self, rhs): """Copy all data from rhs into this instance, handles usage count""" self._manager = rhs._manager self._rlist = type(rhs._rlist)(rhs._rlist) self._region = rhs._region self._ofs = rhs._ofs self._size = rhs._size for region in self._rlist: region.increment_client_count() if self._region is not None: self._region.increment_client_count() # END handle regions def __copy__(self): """copy module interface""" cpy = type(self)() cpy._copy_from(self) return cpy #{ Interface def assign(self, rhs): """Assign rhs to this instance. This is required in order to get a real copy. Alternativly, you can copy an existing instance using the copy module""" self._destroy() self._copy_from(rhs) def use_region(self, offset=0, size=0, flags=0): """Assure we point to a window which allows access to the given offset into the file :param offset: absolute offset in bytes into the file :param size: amount of bytes to map. If 0, all available bytes will be mapped :param flags: additional flags to be given to os.open in case a file handle is initially opened for mapping. Has no effect if a region can actually be reused. :return: this instance - it should be queried for whether it points to a valid memory region. This is not the case if the mapping failed because we reached the end of the file **Note:**: The size actually mapped may be smaller than the given size. If that is the case, either the file has reached its end, or the map was created between two existing regions""" need_region = True man = self._manager fsize = self._rlist.file_size() size = min(size or fsize, man.window_size() or fsize) # clamp size to window size if self._region is not None: if self._region.includes_ofs(offset): need_region = False else: self.unuse_region() # END handle existing region # END check existing region # offset too large ? if offset >= fsize: return self # END handle offset if need_region: self._region = man._obtain_region(self._rlist, offset, size, flags, False) self._region.increment_client_count() # END need region handling self._ofs = offset - self._region._b self._size = min(size, self._region.ofs_end() - offset) return self def unuse_region(self): """Unuse the current region. Does nothing if we have no current region **Note:** the cursor unuses the region automatically upon destruction. It is recommended to un-use the region once you are done reading from it in persistent cursors as it helps to free up resource more quickly""" if self._region is not None: self._region.increment_client_count(-1) self._region = None # note: should reset ofs and size, but we spare that for performance. Its not # allowed to query information if we are not valid ! def buffer(self): """Return a buffer object which allows access to our memory region from our offset to the window size. Please note that it might be smaller than you requested when calling use_region() **Note:** You can only obtain a buffer if this instance is_valid() ! **Note:** buffers should not be cached passed the duration of your access as it will prevent resources from being freed even though they might not be accounted for anymore !""" return buffer(self._region.buffer(), self._ofs, self._size) def map(self): """ :return: the underlying raw memory map. Please not that the offset and size is likely to be different to what you set as offset and size. Use it only if you are sure about the region it maps, which is the whole file in case of StaticWindowMapManager""" return self._region.map() def is_valid(self): """:return: True if we have a valid and usable region""" return self._region is not None def is_associated(self): """:return: True if we are associated with a specific file already""" return self._rlist is not None def ofs_begin(self): """:return: offset to the first byte pointed to by our cursor **Note:** only if is_valid() is True""" return self._region._b + self._ofs def ofs_end(self): """:return: offset to one past the last available byte""" # unroll method calls for performance ! return self._region._b + self._ofs + self._size def size(self): """:return: amount of bytes we point to""" return self._size def region(self): """:return: our mapped region, or None if nothing is mapped yet :raise AssertionError: if we have no current region. This is only useful for debugging""" return self._region def includes_ofs(self, ofs): """:return: True if the given absolute offset is contained in the cursors current region **Note:** cursor must be valid for this to work""" # unroll methods return (self._region._b + self._ofs) <= ofs < (self._region._b + self._ofs + self._size) def file_size(self): """:return: size of the underlying file""" return self._rlist.file_size() def path_or_fd(self): """:return: path or file descriptor of the underlying mapped file""" return self._rlist.path_or_fd() def path(self): """:return: path of the underlying mapped file :raise ValueError: if attached path is not a path""" if isinstance(self._rlist.path_or_fd(), int): raise ValueError("Path queried although mapping was applied to a file descriptor") # END handle type return self._rlist.path_or_fd() def fd(self): """:return: file descriptor used to create the underlying mapping. **Note:** it is not required to be valid anymore :raise ValueError: if the mapping was not created by a file descriptor""" if isinstance(self._rlist.path_or_fd(), string_types()): raise ValueError("File descriptor queried although mapping was generated from path") # END handle type return self._rlist.path_or_fd() #} END interface class StaticWindowMapManager(object): """Provides a manager which will produce single size cursors that are allowed to always map the whole file. Clients must be written to specifically know that they are accessing their data through a StaticWindowMapManager, as they otherwise have to deal with their window size. These clients would have to use a SlidingWindowMapBuffer to hide this fact. This type will always use a maximum window size, and optimize certain methods to accommodate this fact""" __slots__ = [ '_fdict', # mapping of path -> StorageHelper (of some kind '_window_size', # maximum size of a window '_max_memory_size', # maximum amount of memory we may allocate '_max_handle_count', # maximum amount of handles to keep open '_memory_size', # currently allocated memory size '_handle_count', # amount of currently allocated file handles ] #{ Configuration MapRegionListCls = MapRegionList MapWindowCls = MapWindow MapRegionCls = MapRegion WindowCursorCls = WindowCursor #} END configuration _MB_in_bytes = 1024 * 1024 def __init__(self, window_size=0, max_memory_size=0, max_open_handles=sys.maxsize): """initialize the manager with the given parameters. :param window_size: if -1, a default window size will be chosen depending on the operating system's architecture. It will internally be quantified to a multiple of the page size If 0, the window may have any size, which basically results in mapping the whole file at one :param max_memory_size: maximum amount of memory we may map at once before releasing mapped regions. If 0, a viable default will be set depending on the system's architecture. It is a soft limit that is tried to be kept, but nothing bad happens if we have to over-allocate :param max_open_handles: if not maxint, limit the amount of open file handles to the given number. Otherwise the amount is only limited by the system itself. If a system or soft limit is hit, the manager will free as many handles as possible""" self._fdict = dict() self._window_size = window_size self._max_memory_size = max_memory_size self._max_handle_count = max_open_handles self._memory_size = 0 self._handle_count = 0 if window_size < 0: coeff = 64 if is_64_bit(): coeff = 1024 # END handle arch self._window_size = coeff * self._MB_in_bytes # END handle max window size if max_memory_size == 0: coeff = 1024 if is_64_bit(): coeff = 8192 # END handle arch self._max_memory_size = coeff * self._MB_in_bytes # END handle max memory size #{ Internal Methods def _collect_lru_region(self, size): """Unmap the region which was least-recently used and has no client :param size: size of the region we want to map next (assuming its not already mapped partially or full if 0, we try to free any available region :return: Amount of freed regions .. Note:: We don't raise exceptions anymore, in order to keep the system working, allowing temporary overallocation. If the system runs out of memory, it will tell. .. TODO:: implement a case where all unusued regions are discarded efficiently. Currently its only brute force """ num_found = 0 while (size == 0) or (self._memory_size + size > self._max_memory_size): lru_region = None lru_list = None for regions in self._fdict.values(): for region in regions: # check client count - if it's 1, it's just us if (region.client_count() == 1 and (lru_region is None or region._uc < lru_region._uc)): lru_region = region lru_list = regions # END update lru_region # END for each region # END for each regions list if lru_region is None: break # END handle region not found num_found += 1 del(lru_list[lru_list.index(lru_region)]) lru_region.increment_client_count(-1) self._memory_size -= lru_region.size() self._handle_count -= 1 # END while there is more memory to free return num_found def _obtain_region(self, a, offset, size, flags, is_recursive): """Utilty to create a new region - for more information on the parameters, see MapCursor.use_region. :param a: A regions (a)rray :return: The newly created region""" if self._memory_size + size > self._max_memory_size: self._collect_lru_region(size) # END handle collection r = None if a: assert len(a) == 1 r = a[0] else: try: r = self.MapRegionCls(a.path_or_fd(), 0, sys.maxsize, flags) except Exception: # apparently we are out of system resources or hit a limit # As many more operations are likely to fail in that condition ( # like reading a file from disk, etc) we free up as much as possible # As this invalidates our insert position, we have to recurse here if is_recursive: # we already tried this, and still have no success in obtaining # a mapping. This is an exception, so we propagate it raise # END handle existing recursion self._collect_lru_region(0) return self._obtain_region(a, offset, size, flags, True) # END handle exceptions self._handle_count += 1 self._memory_size += r.size() a.append(r) # END handle array assert r.includes_ofs(offset) return r #}END internal methods #{ Interface def make_cursor(self, path_or_fd): """ :return: a cursor pointing to the given path or file descriptor. It can be used to map new regions of the file into memory **Note:** if a file descriptor is given, it is assumed to be open and valid, but may be closed afterwards. To refer to the same file, you may reuse your existing file descriptor, but keep in mind that new windows can only be mapped as long as it stays valid. This is why the using actual file paths are preferred unless you plan to keep the file descriptor open. **Note:** file descriptors are problematic as they are not necessarily unique, as two different files opened and closed in succession might have the same file descriptor id. **Note:** Using file descriptors directly is faster once new windows are mapped as it prevents the file to be opened again just for the purpose of mapping it.""" regions = self._fdict.get(path_or_fd) if regions is None: regions = self.MapRegionListCls(path_or_fd) self._fdict[path_or_fd] = regions # END obtain region for path return self.WindowCursorCls(self, regions) def collect(self): """Collect all available free-to-collect mapped regions :return: Amount of freed handles""" return self._collect_lru_region(0) def num_file_handles(self): """:return: amount of file handles in use. Each mapped region uses one file handle""" return self._handle_count def num_open_files(self): """Amount of opened files in the system""" return reduce(lambda x, y: x + y, (1 for rlist in self._fdict.values() if len(rlist) > 0), 0) def window_size(self): """:return: size of each window when allocating new regions""" return self._window_size def mapped_memory_size(self): """:return: amount of bytes currently mapped in total""" return self._memory_size def max_file_handles(self): """:return: maximium amount of handles we may have opened""" return self._max_handle_count def max_mapped_memory_size(self): """:return: maximum amount of memory we may allocate""" return self._max_memory_size #} END interface #{ Special Purpose Interface def force_map_handle_removal_win(self, base_path): """ONLY AVAILABLE ON WINDOWS On windows removing files is not allowed if anybody still has it opened. If this process is ourselves, and if the whole process uses this memory manager (as far as the parent framework is concerned) we can enforce closing all memory maps whose path matches the given base path to allow the respective operation after all. The respective system must NOT access the closed memory regions anymore ! This really may only be used if you know that the items which keep the cursors alive will not be using it anymore. They need to be recreated ! :return: Amount of closed handles **Note:** does nothing on non-windows platforms""" if sys.platform != 'win32': return # END early bailout num_closed = 0 for path, rlist in self._fdict.items(): if path.startswith(base_path): for region in rlist: region.release() num_closed += 1 # END path matches # END for each path return num_closed #} END special purpose interface class SlidingWindowMapManager(StaticWindowMapManager): """Maintains a list of ranges of mapped memory regions in one or more files and allows to easily obtain additional regions assuring there is no overlap. Once a certain memory limit is reached globally, or if there cannot be more open file handles which result from each mmap call, the least recently used, and currently unused mapped regions are unloaded automatically. **Note:** currently not thread-safe ! **Note:** in the current implementation, we will automatically unload windows if we either cannot create more memory maps (as the open file handles limit is hit) or if we have allocated more than a safe amount of memory already, which would possibly cause memory allocations to fail as our address space is full.""" __slots__ = tuple() def __init__(self, window_size=-1, max_memory_size=0, max_open_handles=sys.maxsize): """Adjusts the default window size to -1""" super(SlidingWindowMapManager, self).__init__(window_size, max_memory_size, max_open_handles) def _obtain_region(self, a, offset, size, flags, is_recursive): # bisect to find an existing region. The c++ implementation cannot # do that as it uses a linked list for regions. r = None lo = 0 hi = len(a) while lo < hi: mid = (lo + hi) // 2 ofs = a[mid]._b if ofs <= offset: if a[mid].includes_ofs(offset): r = a[mid] break # END have region lo = mid + 1 else: hi = mid # END handle position # END while bisecting if r is None: window_size = self._window_size left = self.MapWindowCls(0, 0) mid = self.MapWindowCls(offset, size) right = self.MapWindowCls(a.file_size(), 0) # we want to honor the max memory size, and assure we have anough # memory available # Save calls ! if self._memory_size + window_size > self._max_memory_size: self._collect_lru_region(window_size) # END handle collection # we assume the list remains sorted by offset insert_pos = 0 len_regions = len(a) if len_regions == 1: if a[0]._b <= offset: insert_pos = 1 # END maintain sort else: # find insert position insert_pos = len_regions for i, region in enumerate(a): if region._b > offset: insert_pos = i break # END if insert position is correct # END for each region # END obtain insert pos # adjust the actual offset and size values to create the largest # possible mapping if insert_pos == 0: if len_regions: right = self.MapWindowCls.from_region(a[insert_pos]) # END adjust right side else: if insert_pos != len_regions: right = self.MapWindowCls.from_region(a[insert_pos]) # END adjust right window left = self.MapWindowCls.from_region(a[insert_pos - 1]) # END adjust surrounding windows mid.extend_left_to(left, window_size) mid.extend_right_to(right, window_size) mid.align() # it can happen that we align beyond the end of the file if mid.ofs_end() > right.ofs: mid.size = right.ofs - mid.ofs # END readjust size # insert new region at the right offset to keep the order try: if self._handle_count >= self._max_handle_count: raise Exception # END assert own imposed max file handles r = self.MapRegionCls(a.path_or_fd(), mid.ofs, mid.size, flags) except Exception: # apparently we are out of system resources or hit a limit # As many more operations are likely to fail in that condition ( # like reading a file from disk, etc) we free up as much as possible # As this invalidates our insert position, we have to recurse here if is_recursive: # we already tried this, and still have no success in obtaining # a mapping. This is an exception, so we propagate it raise # END handle existing recursion self._collect_lru_region(0) return self._obtain_region(a, offset, size, flags, True) # END handle exceptions self._handle_count += 1 self._memory_size += r.size() a.insert(insert_pos, r) # END create new region return r smmap2-2.0.1/smmap/test/0000755000076600000240000000000013002673663015270 5ustar byronstaff00000000000000smmap2-2.0.1/smmap/test/__init__.py0000644000076600000240000000000012637461251017370 0ustar byronstaff00000000000000smmap2-2.0.1/smmap/test/lib.py0000644000076600000240000000267412776377451016436 0ustar byronstaff00000000000000"""Provide base classes for the test system""" from unittest import TestCase import os import tempfile __all__ = ['TestBase', 'FileCreator'] #{ Utilities class FileCreator(object): """A instance which creates a temporary file with a prefix and a given size and provides this info to the user. Once it gets deleted, it will remove the temporary file as well.""" __slots__ = ("_size", "_path") def __init__(self, size, prefix=''): assert size, "Require size to be larger 0" self._path = tempfile.mktemp(prefix=prefix) self._size = size with open(self._path, "wb") as fp: fp.seek(size - 1) fp.write(b'1') assert os.path.getsize(self.path) == size def __del__(self): try: os.remove(self.path) except OSError: pass # END exception handling def __enter__(self): return self def __exit__(self, exc_type, exc_value, traceback): self.__del__() @property def path(self): return self._path @property def size(self): return self._size #} END utilities class TestBase(TestCase): """Foundation used by all tests""" #{ Configuration k_window_test_size = 1000 * 1000 * 8 + 5195 #} END configuration #{ Overrides @classmethod def setUpAll(cls): # nothing for now pass # END overrides #{ Interface #} END interface smmap2-2.0.1/smmap/test/test_buf.py0000644000076600000240000001254612776377451017502 0ustar byronstaff00000000000000from __future__ import print_function from .lib import TestBase, FileCreator from smmap.mman import ( SlidingWindowMapManager, StaticWindowMapManager ) from smmap.buf import SlidingWindowMapBuffer from random import randint from time import time import sys import os man_optimal = SlidingWindowMapManager() man_worst_case = SlidingWindowMapManager( window_size=TestBase.k_window_test_size // 100, max_memory_size=TestBase.k_window_test_size // 3, max_open_handles=15) static_man = StaticWindowMapManager() class TestBuf(TestBase): def test_basics(self): with FileCreator(self.k_window_test_size, "buffer_test") as fc: # invalid paths fail upon construction c = man_optimal.make_cursor(fc.path) self.assertRaises(ValueError, SlidingWindowMapBuffer, type(c)()) # invalid cursor self.assertRaises(ValueError, SlidingWindowMapBuffer, c, fc.size) # offset too large buf = SlidingWindowMapBuffer() # can create uninitailized buffers assert buf.cursor() is None # can call end access any time buf.end_access() buf.end_access() assert len(buf) == 0 # begin access can revive it, if the offset is suitable offset = 100 assert buf.begin_access(c, fc.size) == False assert buf.begin_access(c, offset) == True assert len(buf) == fc.size - offset assert buf.cursor().is_valid() # empty begin access keeps it valid on the same path, but alters the offset assert buf.begin_access() == True assert len(buf) == fc.size assert buf.cursor().is_valid() # simple access with open(fc.path, 'rb') as fp: data = fp.read() assert data[offset] == buf[0] assert data[offset:offset * 2] == buf[0:offset] # negative indices, partial slices assert buf[-1] == buf[len(buf) - 1] assert buf[-10:] == buf[len(buf) - 10:len(buf)] # end access makes its cursor invalid buf.end_access() assert not buf.cursor().is_valid() assert buf.cursor().is_associated() # but it remains associated # an empty begin access fixes it up again assert buf.begin_access() == True and buf.cursor().is_valid() del(buf) # ends access automatically del(c) assert man_optimal.num_file_handles() == 1 # PERFORMANCE # blast away with random access and a full mapping - we don't want to # exaggerate the manager's overhead, but measure the buffer overhead # We do it once with an optimal setting, and with a worse manager which # will produce small mappings only ! max_num_accesses = 100 fd = os.open(fc.path, os.O_RDONLY) for item in (fc.path, fd): for manager, man_id in ((man_optimal, 'optimal'), (man_worst_case, 'worst case'), (static_man, 'static optimal')): buf = SlidingWindowMapBuffer(manager.make_cursor(item)) assert manager.num_file_handles() == 1 for access_mode in range(2): # single, multi num_accesses_left = max_num_accesses num_bytes = 0 fsize = fc.size st = time() buf.begin_access() while num_accesses_left: num_accesses_left -= 1 if access_mode: # multi ofs_start = randint(0, fsize) ofs_end = randint(ofs_start, fsize) d = buf[ofs_start:ofs_end] assert len(d) == ofs_end - ofs_start assert d == data[ofs_start:ofs_end] num_bytes += len(d) del d else: pos = randint(0, fsize) assert buf[pos] == data[pos] num_bytes += 1 # END handle mode # END handle num accesses buf.end_access() assert manager.num_file_handles() assert manager.collect() assert manager.num_file_handles() == 0 elapsed = max(time() - st, 0.001) # prevent zero division errors on windows mb = float(1000 * 1000) mode_str = (access_mode and "slice") or "single byte" print("%s: Made %i random %s accesses to buffer created from %s reading a total of %f mb in %f s (%f mb/s)" % (man_id, max_num_accesses, mode_str, type(item), num_bytes / mb, elapsed, (num_bytes / mb) / elapsed), file=sys.stderr) # END handle access mode del buf # END for each manager # END for each input os.close(fd) smmap2-2.0.1/smmap/test/test_mman.py0000644000076600000240000002515112776377451017652 0ustar byronstaff00000000000000from __future__ import print_function from .lib import TestBase, FileCreator from smmap.mman import ( WindowCursor, SlidingWindowMapManager, StaticWindowMapManager ) from smmap.util import align_to_mmap from random import randint from time import time import os import sys from copy import copy class TestMMan(TestBase): def test_cursor(self): with FileCreator(self.k_window_test_size, "cursor_test") as fc: man = SlidingWindowMapManager() ci = WindowCursor(man) # invalid cursor assert not ci.is_valid() assert not ci.is_associated() assert ci.size() == 0 # this is cached, so we can query it in invalid state cv = man.make_cursor(fc.path) assert not cv.is_valid() # no region mapped yet assert cv.is_associated() # but it know where to map it from assert cv.file_size() == fc.size assert cv.path() == fc.path # copy module cio = copy(cv) assert not cio.is_valid() and cio.is_associated() # assign method assert not ci.is_associated() ci.assign(cv) assert not ci.is_valid() and ci.is_associated() # unuse non-existing region is fine cv.unuse_region() cv.unuse_region() # destruction is fine (even multiple times) cv._destroy() WindowCursor(man)._destroy() def test_memory_manager(self): slide_man = SlidingWindowMapManager() static_man = StaticWindowMapManager() for man in (static_man, slide_man): assert man.num_file_handles() == 0 assert man.num_open_files() == 0 winsize_cmp_val = 0 if isinstance(man, StaticWindowMapManager): winsize_cmp_val = -1 # END handle window size assert man.window_size() > winsize_cmp_val assert man.mapped_memory_size() == 0 assert man.max_mapped_memory_size() > 0 # collection doesn't raise in 'any' mode man._collect_lru_region(0) # doesn't raise if we are within the limit man._collect_lru_region(10) # doesn't fail if we over-allocate assert man._collect_lru_region(sys.maxsize) == 0 # use a region, verify most basic functionality with FileCreator(self.k_window_test_size, "manager_test") as fc: fd = os.open(fc.path, os.O_RDONLY) try: for item in (fc.path, fd): c = man.make_cursor(item) assert c.path_or_fd() is item assert c.use_region(10, 10).is_valid() assert c.ofs_begin() == 10 assert c.size() == 10 with open(fc.path, 'rb') as fp: assert c.buffer()[:] == fp.read(20)[10:] if isinstance(item, int): self.assertRaises(ValueError, c.path) else: self.assertRaises(ValueError, c.fd) # END handle value error # END for each input finally: os.close(fd) # END for each manasger type def test_memman_operation(self): # test more access, force it to actually unmap regions with FileCreator(self.k_window_test_size, "manager_operation_test") as fc: with open(fc.path, 'rb') as fp: data = fp.read() fd = os.open(fc.path, os.O_RDONLY) try: max_num_handles = 15 # small_size = for mtype, args in ((StaticWindowMapManager, (0, fc.size // 3, max_num_handles)), (SlidingWindowMapManager, (fc.size // 100, fc.size // 3, max_num_handles)),): for item in (fc.path, fd): assert len(data) == fc.size # small windows, a reasonable max memory. Not too many regions at once man = mtype(window_size=args[0], max_memory_size=args[1], max_open_handles=args[2]) c = man.make_cursor(item) # still empty (more about that is tested in test_memory_manager() assert man.num_open_files() == 0 assert man.mapped_memory_size() == 0 base_offset = 5000 # window size is 0 for static managers, hence size will be 0. We take that into consideration size = man.window_size() // 2 assert c.use_region(base_offset, size).is_valid() rr = c.region() assert rr.client_count() == 2 # the manager and the cursor and us assert man.num_open_files() == 1 assert man.num_file_handles() == 1 assert man.mapped_memory_size() == rr.size() # assert c.size() == size # the cursor may overallocate in its static version assert c.ofs_begin() == base_offset assert rr.ofs_begin() == 0 # it was aligned and expanded if man.window_size(): # but isn't larger than the max window (aligned) assert rr.size() == align_to_mmap(man.window_size(), True) else: assert rr.size() == fc.size # END ignore static managers which dont use windows and are aligned to file boundaries assert c.buffer()[:] == data[base_offset:base_offset + (size or c.size())] # obtain second window, which spans the first part of the file - it is a still the same window nsize = (size or fc.size) - 10 assert c.use_region(0, nsize).is_valid() assert c.region() == rr assert man.num_file_handles() == 1 assert c.size() == nsize assert c.ofs_begin() == 0 assert c.buffer()[:] == data[:nsize] # map some part at the end, our requested size cannot be kept overshoot = 4000 base_offset = fc.size - (size or c.size()) + overshoot assert c.use_region(base_offset, size).is_valid() if man.window_size(): assert man.num_file_handles() == 2 assert c.size() < size assert c.region() is not rr # old region is still available, but has not curser ref anymore assert rr.client_count() == 1 # only held by manager else: assert c.size() < fc.size # END ignore static managers which only have one handle per file rr = c.region() assert rr.client_count() == 2 # manager + cursor assert rr.ofs_begin() < c.ofs_begin() # it should have extended itself to the left assert rr.ofs_end() <= fc.size # it cannot be larger than the file assert c.buffer()[:] == data[base_offset:base_offset + (size or c.size())] # unising a region makes the cursor invalid c.unuse_region() assert not c.is_valid() if man.window_size(): # but doesn't change anything regarding the handle count - we cache it and only # remove mapped regions if we have to assert man.num_file_handles() == 2 # END ignore this for static managers # iterate through the windows, verify data contents # this will trigger map collection after a while max_random_accesses = 5000 num_random_accesses = max_random_accesses memory_read = 0 st = time() # cache everything to get some more performance includes_ofs = c.includes_ofs max_mapped_memory_size = man.max_mapped_memory_size() max_file_handles = man.max_file_handles() mapped_memory_size = man.mapped_memory_size num_file_handles = man.num_file_handles while num_random_accesses: num_random_accesses -= 1 base_offset = randint(0, fc.size - 1) # precondition if man.window_size(): assert max_mapped_memory_size >= mapped_memory_size() # END statics will overshoot, which is fine assert max_file_handles >= num_file_handles() assert c.use_region(base_offset, (size or c.size())).is_valid() csize = c.size() assert c.buffer()[:] == data[base_offset:base_offset + csize] memory_read += csize assert includes_ofs(base_offset) assert includes_ofs(base_offset + csize - 1) assert not includes_ofs(base_offset + csize) # END while we should do an access elapsed = max(time() - st, 0.001) # prevent zero divison errors on windows mb = float(1000 * 1000) print("%s: Read %i mb of memory with %i random on cursor initialized with %s accesses in %fs (%f mb/s)\n" % (mtype, memory_read / mb, max_random_accesses, type(item), elapsed, (memory_read / mb) / elapsed), file=sys.stderr) # an offset as large as the size doesn't work ! assert not c.use_region(fc.size, size).is_valid() # collection - it should be able to collect all assert man.num_file_handles() assert man.collect() assert man.num_file_handles() == 0 # END for each item # END for each manager type finally: os.close(fd) smmap2-2.0.1/smmap/test/test_tutorial.py0000644000076600000240000000667012776377451020572 0ustar byronstaff00000000000000from .lib import TestBase class TestTutorial(TestBase): def test_example(self): # Memory Managers ################## import smmap # This instance should be globally available in your application # It is configured to be well suitable for 32-bit or 64 bit applications. mman = smmap.SlidingWindowMapManager() # the manager provides much useful information about its current state # like the amount of open file handles or the amount of mapped memory assert mman.num_file_handles() == 0 assert mman.mapped_memory_size() == 0 # and many more ... # Cursors ########## import smmap.test.lib with smmap.test.lib.FileCreator(1024 * 1024 * 8, "test_file") as fc: # obtain a cursor to access some file. c = mman.make_cursor(fc.path) # the cursor is now associated with the file, but not yet usable assert c.is_associated() assert not c.is_valid() # before you can use the cursor, you have to specify a window you want to # access. The following just says you want as much data as possible starting # from offset 0. # To be sure your region could be mapped, query for validity assert c.use_region().is_valid() # use_region returns self # once a region was mapped, you must query its dimension regularly # to assure you don't try to access its buffer out of its bounds assert c.size() c.buffer()[0] # first byte c.buffer()[1:10] # first 9 bytes c.buffer()[c.size() - 1] # last byte # its recommended not to create big slices when feeding the buffer # into consumers (e.g. struct or zlib). # Instead, either give the buffer directly, or use pythons buffer command. from smmap.util import buffer buffer(c.buffer(), 1, 9) # first 9 bytes without copying them # you can query absolute offsets, and check whether an offset is included # in the cursor's data. assert c.ofs_begin() < c.ofs_end() assert c.includes_ofs(100) # If you are over out of bounds with one of your region requests, the # cursor will be come invalid. It cannot be used in that state assert not c.use_region(fc.size, 100).is_valid() # map as much as possible after skipping the first 100 bytes assert c.use_region(100).is_valid() # You can explicitly free cursor resources by unusing the cursor's region c.unuse_region() assert not c.is_valid() # Buffers ######### # Create a default buffer which can operate on the whole file buf = smmap.SlidingWindowMapBuffer(mman.make_cursor(fc.path)) # you can use it right away assert buf.cursor().is_valid() buf[0] # access the first byte buf[-1] # access the last ten bytes on the file buf[-10:] # access the last ten bytes # If you want to keep the instance between different accesses, use the # dedicated methods buf.end_access() assert not buf.cursor().is_valid() # you cannot use the buffer anymore assert buf.begin_access(offset=10) # start using the buffer at an offset smmap2-2.0.1/smmap/test/test_util.py0000644000076600000240000000661412776377451017702 0ustar byronstaff00000000000000from .lib import TestBase, FileCreator from smmap.util import ( MapWindow, MapRegion, MapRegionList, ALLOCATIONGRANULARITY, is_64_bit, align_to_mmap ) import os import sys class TestMMan(TestBase): def test_window(self): wl = MapWindow(0, 1) # left wc = MapWindow(1, 1) # center wc2 = MapWindow(10, 5) # another center wr = MapWindow(8000, 50) # right assert wl.ofs_end() == 1 assert wc.ofs_end() == 2 assert wr.ofs_end() == 8050 # extension does nothing if already in place maxsize = 100 wc.extend_left_to(wl, maxsize) assert wc.ofs == 1 and wc.size == 1 wl.extend_right_to(wc, maxsize) wl.extend_right_to(wc, maxsize) assert wl.ofs == 0 and wl.size == 1 # an actual left extension pofs_end = wc2.ofs_end() wc2.extend_left_to(wc, maxsize) assert wc2.ofs == wc.ofs_end() and pofs_end == wc2.ofs_end() # respects maxsize wc.extend_right_to(wr, maxsize) assert wc.ofs == 1 and wc.size == maxsize wc.extend_right_to(wr, maxsize) assert wc.ofs == 1 and wc.size == maxsize # without maxsize wc.extend_right_to(wr, sys.maxsize) assert wc.ofs_end() == wr.ofs and wc.ofs == 1 # extend left wr.extend_left_to(wc2, maxsize) wr.extend_left_to(wc2, maxsize) assert wr.size == maxsize wr.extend_left_to(wc2, sys.maxsize) assert wr.ofs == wc2.ofs_end() wc.align() assert wc.ofs == 0 and wc.size == align_to_mmap(wc.size, True) def test_region(self): with FileCreator(self.k_window_test_size, "window_test") as fc: half_size = fc.size // 2 rofs = align_to_mmap(4200, False) rfull = MapRegion(fc.path, 0, fc.size) rhalfofs = MapRegion(fc.path, rofs, fc.size) rhalfsize = MapRegion(fc.path, 0, half_size) # offsets assert rfull.ofs_begin() == 0 and rfull.size() == fc.size assert rfull.ofs_end() == fc.size # if this method works, it works always assert rhalfofs.ofs_begin() == rofs and rhalfofs.size() == fc.size - rofs assert rhalfsize.ofs_begin() == 0 and rhalfsize.size() == half_size assert rfull.includes_ofs(0) and rfull.includes_ofs(fc.size - 1) and rfull.includes_ofs(half_size) assert not rfull.includes_ofs(-1) and not rfull.includes_ofs(sys.maxsize) # auto-refcount assert rfull.client_count() == 1 rfull2 = rfull assert rfull.client_count() == 1, "no auto-counting" # window constructor w = MapWindow.from_region(rfull) assert w.ofs == rfull.ofs_begin() and w.ofs_end() == rfull.ofs_end() def test_region_list(self): with FileCreator(100, "sample_file") as fc: fd = os.open(fc.path, os.O_RDONLY) try: for item in (fc.path, fd): ml = MapRegionList(item) assert len(ml) == 0 assert ml.path_or_fd() == item assert ml.file_size() == fc.size finally: os.close(fd) def test_util(self): assert isinstance(is_64_bit(), bool) # just call it assert align_to_mmap(1, False) == 0 assert align_to_mmap(1, True) == ALLOCATIONGRANULARITY smmap2-2.0.1/smmap/util.py0000644000076600000240000002213013002673431015627 0ustar byronstaff00000000000000"""Module containing a memory memory manager which provides a sliding window on a number of memory mapped files""" import os import sys from mmap import mmap, ACCESS_READ try: from mmap import ALLOCATIONGRANULARITY except ImportError: # in python pre 2.6, the ALLOCATIONGRANULARITY does not exist as it is mainly # useful for aligning the offset. The offset argument doesn't exist there though from mmap import PAGESIZE as ALLOCATIONGRANULARITY # END handle pythons missing quality assurance __all__ = ["align_to_mmap", "is_64_bit", "buffer", "MapWindow", "MapRegion", "MapRegionList", "ALLOCATIONGRANULARITY"] #{ Utilities try: # Python 2 buffer = buffer except NameError: # Python 3 has no `buffer`; only `memoryview` def buffer(obj, offset, size): # Actually, for gitpython this is fastest ... . return memoryview(obj)[offset:offset+size] # doing it directly is much faster ! # return obj[offset:offset + size] def string_types(): if sys.version_info[0] >= 3: return str else: return basestring def align_to_mmap(num, round_up): """ Align the given integer number to the closest page offset, which usually is 4096 bytes. :param round_up: if True, the next higher multiple of page size is used, otherwise the lower page_size will be used (i.e. if True, 1 becomes 4096, otherwise it becomes 0) :return: num rounded to closest page""" res = (num // ALLOCATIONGRANULARITY) * ALLOCATIONGRANULARITY if round_up and (res != num): res += ALLOCATIONGRANULARITY # END handle size return res def is_64_bit(): """:return: True if the system is 64 bit. Otherwise it can be assumed to be 32 bit""" return sys.maxsize > (1 << 32) - 1 #}END utilities #{ Utility Classes class MapWindow(object): """Utility type which is used to snap windows towards each other, and to adjust their size""" __slots__ = ( 'ofs', # offset into the file in bytes 'size' # size of the window in bytes ) def __init__(self, offset, size): self.ofs = offset self.size = size def __repr__(self): return "MapWindow(%i, %i)" % (self.ofs, self.size) @classmethod def from_region(cls, region): """:return: new window from a region""" return cls(region._b, region.size()) def ofs_end(self): return self.ofs + self.size def align(self): """Assures the previous window area is contained in the new one""" nofs = align_to_mmap(self.ofs, 0) self.size += self.ofs - nofs # keep size constant self.ofs = nofs self.size = align_to_mmap(self.size, 1) def extend_left_to(self, window, max_size): """Adjust the offset to start where the given window on our left ends if possible, but don't make yourself larger than max_size. The resize will assure that the new window still contains the old window area""" rofs = self.ofs - window.ofs_end() nsize = rofs + self.size rofs -= nsize - min(nsize, max_size) self.ofs = self.ofs - rofs self.size += rofs def extend_right_to(self, window, max_size): """Adjust the size to make our window end where the right window begins, but don't get larger than max_size""" self.size = min(self.size + (window.ofs - self.ofs_end()), max_size) class MapRegion(object): """Defines a mapped region of memory, aligned to pagesizes **Note:** deallocates used region automatically on destruction""" __slots__ = [ '_b', # beginning of mapping '_mf', # mapped memory chunk (as returned by mmap) '_uc', # total amount of usages '_size', # cached size of our memory map '__weakref__' ] _need_compat_layer = sys.version_info[:2] < (2, 6) if _need_compat_layer: __slots__.append('_mfb') # mapped memory buffer to provide offset # END handle additional slot #{ Configuration #} END configuration def __init__(self, path_or_fd, ofs, size, flags=0): """Initialize a region, allocate the memory map :param path_or_fd: path to the file to map, or the opened file descriptor :param ofs: **aligned** offset into the file to be mapped :param size: if size is larger then the file on disk, the whole file will be allocated the the size automatically adjusted :param flags: additional flags to be given when opening the file. :raise Exception: if no memory can be allocated""" self._b = ofs self._size = 0 self._uc = 0 if isinstance(path_or_fd, int): fd = path_or_fd else: fd = os.open(path_or_fd, os.O_RDONLY | getattr(os, 'O_BINARY', 0) | flags) # END handle fd try: kwargs = dict(access=ACCESS_READ, offset=ofs) corrected_size = size sizeofs = ofs if self._need_compat_layer: del(kwargs['offset']) corrected_size += ofs sizeofs = 0 # END handle python not supporting offset ! Arg # have to correct size, otherwise (instead of the c version) it will # bark that the size is too large ... many extra file accesses because # if this ... argh ! actual_size = min(os.fstat(fd).st_size - sizeofs, corrected_size) self._mf = mmap(fd, actual_size, **kwargs) # END handle memory mode self._size = len(self._mf) if self._need_compat_layer: self._mfb = buffer(self._mf, ofs, self._size) # END handle buffer wrapping finally: if isinstance(path_or_fd, string_types()): os.close(fd) # END only close it if we opened it # END close file handle # We assume the first one to use us keeps us around self.increment_client_count() def __repr__(self): return "MapRegion<%i, %i>" % (self._b, self.size()) #{ Interface def buffer(self): """:return: a buffer containing the memory""" return self._mf def map(self): """:return: a memory map containing the memory""" return self._mf def ofs_begin(self): """:return: absolute byte offset to the first byte of the mapping""" return self._b def size(self): """:return: total size of the mapped region in bytes""" return self._size def ofs_end(self): """:return: Absolute offset to one byte beyond the mapping into the file""" return self._b + self._size def includes_ofs(self, ofs): """:return: True if the given offset can be read in our mapped region""" return self._b <= ofs < self._b + self._size def client_count(self): """:return: number of clients currently using this region""" return self._uc def increment_client_count(self, ofs = 1): """Adjust the usage count by the given positive or negative offset. If usage count equals 0, we will auto-release our resources :return: True if we released resources, False otherwise. In the latter case, we can still be used""" self._uc += ofs assert self._uc > -1, "Increments must match decrements, usage counter negative: %i" % self._uc if self.client_count() == 0: self.release() return True else: return False # end handle release def release(self): """Release all resources this instance might hold. Must only be called if there usage_count() is zero""" self._mf.close() # re-define all methods which need offset adjustments in compatibility mode if _need_compat_layer: def size(self): return self._size - self._b def ofs_end(self): # always the size - we are as large as it gets return self._size def buffer(self): return self._mfb def includes_ofs(self, ofs): return self._b <= ofs < self._size # END handle compat layer #} END interface class MapRegionList(list): """List of MapRegion instances associating a path with a list of regions.""" __slots__ = ( '_path_or_fd', # path or file descriptor which is mapped by all our regions '_file_size' # total size of the file we map ) def __new__(cls, path): return super(MapRegionList, cls).__new__(cls) def __init__(self, path_or_fd): self._path_or_fd = path_or_fd self._file_size = None def path_or_fd(self): """:return: path or file descriptor we are attached to""" return self._path_or_fd def file_size(self): """:return: size of file we manager""" if self._file_size is None: if isinstance(self._path_or_fd, string_types()): self._file_size = os.stat(self._path_or_fd).st_size else: self._file_size = os.fstat(self._path_or_fd).st_size # END handle path type # END update file size return self._file_size #} END utility classes smmap2-2.0.1/smmap2.egg-info/0000755000076600000240000000000013002673663016065 5ustar byronstaff00000000000000smmap2-2.0.1/smmap2.egg-info/dependency_links.txt0000644000076600000240000000000113002673663022133 0ustar byronstaff00000000000000 smmap2-2.0.1/smmap2.egg-info/PKG-INFO0000644000076600000240000001255713002673663017174 0ustar byronstaff00000000000000Metadata-Version: 1.1 Name: smmap2 Version: 2.0.1 Summary: A pure python implementation of a sliding window memory map manager Home-page: https://github.com/Byron/smmap Author: Sebastian Thiel Author-email: byronimo@gmail.com License: BSD Description: ## Motivation When reading from many possibly large files in a fashion similar to random access, it is usually the fastest and most efficient to use memory maps. Although memory maps have many advantages, they represent a very limited system resource as every map uses one file descriptor, whose amount is limited per process. On 32 bit systems, the amount of memory you can have mapped at a time is naturally limited to theoretical 4GB of memory, which may not be enough for some applications. ## Overview [![Build Status](https://travis-ci.org/gitpython-developers/smmap.svg?branch=master)](https://travis-ci.org/gitpython-developers/smmap) [![Build status](https://ci.appveyor.com/api/projects/status/kuws846av5lvmugo?svg=true&passingText=windows%20OK&failingText=windows%20failed)](https://ci.appveyor.com/project/Byron/smmap) [![Coverage Status](https://coveralls.io/repos/gitpython-developers/smmap/badge.png)](https://coveralls.io/r/gitpython-developers/smmap) [![Issue Stats](http://www.issuestats.com/github/gitpython-developers/smmap/badge/pr)](http://www.issuestats.com/github/gitpython-developers/smmap) [![Issue Stats](http://www.issuestats.com/github/gitpython-developers/smmap/badge/issue)](http://www.issuestats.com/github/gitpython-developers/smmap) Smmap wraps an interface around mmap and tracks the mapped files as well as the amount of clients who use it. If the system runs out of resources, or if a memory limit is reached, it will automatically unload unused maps to allow continued operation. To allow processing large files even on 32 bit systems, it allows only portions of the file to be mapped. Once the user reads beyond the mapped region, smmap will automatically map the next required region, unloading unused regions using a LRU algorithm. The interface also works around the missing offset parameter in python implementations up to python 2.5. Although the library can be used most efficiently with its native interface, a Buffer implementation is provided to hide these details behind a simple string-like interface. For performance critical 64 bit applications, a simplified version of memory mapping is provided which always maps the whole file, but still provides the benefit of unloading unused mappings on demand. ## Prerequisites * Python 2.4, 2.5, 2.6, 2.7 or 3.3 * OSX, Windows or Linux The package was tested on all of the previously mentioned configurations. ## Limitations * The memory access is read-only by design. * In python below 2.6, memory maps will be created in compatibility mode which works, but creates inefficient memory mappings as they always start at offset 0. ## Installing smmap [![Documentation Status](https://readthedocs.org/projects/smmap/badge/?version=latest)](https://readthedocs.org/projects/smmap/?badge=latest) Its easiest to install smmap using the [pip](http://www.pip-installer.org/en/latest) program: ```bash $ pip install smmap ``` As the command will install smmap in your respective python distribution, you will most likely need root permissions to authorize the required changes. If you have downloaded the source archive, the package can be installed by running the `setup.py` script: ```bash $ python setup.py install ``` It is advised to have a look at the **Usage Guide** for a brief introduction on the different database implementations. ## Homepage and Links The project is home on github at https://github.com/gitpython-developers/smmap . The latest source can be cloned from github as well: * git://github.com/gitpython-developers/smmap.git For support, please use the git-python mailing list: * http://groups.google.com/group/git-python Issues can be filed on github: * https://github.com/gitpython-developers/smmap/issues ## License Information *smmap* is licensed under the New BSD License. Platform: any Classifier: Development Status :: 5 - Production/Stable Classifier: Environment :: Console Classifier: Intended Audience :: Developers Classifier: License :: OSI Approved :: BSD License Classifier: Operating System :: OS Independent Classifier: Operating System :: POSIX Classifier: Operating System :: Microsoft :: Windows Classifier: Operating System :: MacOS :: MacOS X Classifier: Programming Language :: Python Classifier: Programming Language :: Python :: 2 Classifier: Programming Language :: Python :: 2.6 Classifier: Programming Language :: Python :: 2.7 Classifier: Programming Language :: Python :: 3 Classifier: Programming Language :: Python :: 3.3 Classifier: Programming Language :: Python :: 3.4 smmap2-2.0.1/smmap2.egg-info/SOURCES.txt0000644000076600000240000000056713002673663017761 0ustar byronstaff00000000000000setup.cfg setup.py smmap/__init__.py smmap/buf.py smmap/exc.py smmap/mman.py smmap/util.py smmap/test/__init__.py smmap/test/lib.py smmap/test/test_buf.py smmap/test/test_mman.py smmap/test/test_tutorial.py smmap/test/test_util.py smmap2.egg-info/PKG-INFO smmap2.egg-info/SOURCES.txt smmap2.egg-info/dependency_links.txt smmap2.egg-info/top_level.txt smmap2.egg-info/zip-safesmmap2-2.0.1/smmap2.egg-info/top_level.txt0000644000076600000240000000000613002673663020613 0ustar byronstaff00000000000000smmap smmap2-2.0.1/smmap2.egg-info/zip-safe0000644000076600000240000000000113000651476017511 0ustar byronstaff00000000000000