1. 17 Sep, 2024 25 commits
  2. 23 Jul, 2024 3 commits
  3. 22 Jul, 2024 1 commit
    • Kirill Smelkov's avatar
      bigfile/zodb: Apply auto format as default only in WCFS mode · 34309058
      Kirill Smelkov authored
      This semantically reverts 99f262dd (bigfile/zodb: Make auto format the
      default) for wendelin.core-1 mode because in non-WCFS mode there are
      known problems with data corruption on BTree topology changes(*) and
      auto mode actually does change those topologies with first setting
      ZBigFile[blk] -> ZBlk1 and then updating the same block to point to
      ZBlk0 object.
      
      Avoid pressuring those problems and use auto as default only in WCFS
      mode that should handle invalidations with all those BTree topology
      changes well.
      
      The patch is based on suggestion by Levin Zimmermann: nexedi/wendelin.core!20 (comment 212405)
      
      We have to move _default_use_wcfs because now it is invoked at module
      import time and needs to be already defined at the time of the call.
      
      (*) see nexedi/wendelin.core@8c32c9f6 for details.
      
      /reviewed-by @levin.zimmermann
      /reviewed-on nexedi/wendelin.core!29
      34309058
  4. 25 Jun, 2024 6 commits
    • Carlos Ramos Carreño's avatar
      wcfs: _mntpt_4zurl: Fix it to accept strings. · 07087ec8
      Carlos Ramos Carreño authored
      Strings cannot be directly hashed without encoding them first, or
      an error will be raised:
      
      ```python
      ______________________________ test_zsync_resync _______________________________
      
          @func
          def test_zsync_resync():
              zstor = testdb.getZODBStorage()
              defer(zstor.close)
      
      >       db, zconn, wconn = _zsync_setup(zstor)
      
      wcfs/client/_wczsync_test.py:112:
      _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
      ../../venvs/wendelin.core/lib/python3.9/site-packages/decorator.py:232: in fun
          return caller(func, *(extras + args), **kw)
      ../pygolang/golang/__init__.py:125: in _
          return f(*argv, **kw)
      wcfs/client/_wczsync_test.py:53: in _zsync_setup
          wc = wcfs.join(zurl)
      wcfs/__init__.py:201: in join
          mntpt = _mntpt_4zurl(zurl)
      _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
      
      zurl = 'file:///srv/slapgrid/slappart66/tmp/testdb_fs.xstpbg49/1.fs'
      
          def _mntpt_4zurl(zurl):
              # normalize zurl so that even if we have e.g. two neos:// urls coming
              # with different paths to ssl keys, or with different order in the list of
              # masters, we still have them associated with the same wcfs mountpoint.
              zurl = zurl_normalize_main(zurl)
      
              m = hashlib.sha1()
      >       m.update(zurl)
      E       TypeError: Strings must be encoded before hashing
      ```
      
      We fix this error by encoding the string as UTF8 before hashing it.
      
      --------
      kirr:
      
      Use b instead of doing
      
          if isinstance(zurl, six.text_type):
            zurl = zurl.encode("utf-8")
      
      wcfs already takes this approach of using b in other places - for
      example in tDB.change:
      
          # change schedules zf to be changed according to changeDelta at commit.
          #
          # changeDelta: {} blk -> data.
          # data can be both bytes and unicode.              <-- NOTE
          def change(t, zf, changeDelta):
              assert isinstance(zf, ZBigFile)
              zfDelta = t._changed.setdefault(zf, {})
              for blk, data in six.iteritems(changeDelta):
                  data = b(data)                             <-- NOTE
                  ...
      
      /reviewed-by @kirr
      /reviewed-on nexedi/wendelin.core!27
      07087ec8
    • Carlos Ramos Carreño's avatar
      wcfs: tests: Adapt changed modules/methods to Python 3. · 594ff3fa
      Carlos Ramos Carreño authored
      Some modules and methods have changed names in Python 3.
      The `thread` module has been renamed to `_thread` and the old name
      gives error when run on Python 3:
      
      ```python
      Traceback:
      /opt/slapgrid/b0df76c24a1d2728ccf3e276f07c1790/parts/python3/lib/python3.9/importlib/__init__.py:127: in import_module
          return _bootstrap._gcd_import(name[level:], package, level)
      wcfs/client/client_test.py:32: in <module>
          from wendelin.wcfs.wcfs_test import tDB, tAt, timeout, eprint
      wcfs/wcfs_test.py:44: in <module>
          from thread import get_ident as gettid
      E   ModuleNotFoundError: No module named 'thread'
      ```
      
      In a similar vein, the `items` method of dictionaries plays the same
      role as the old `iteritems`.
      
      We use the `six` module to paper over these differences.
      
      /reviewed-by @kirr
      /reviewed-on nexedi/wendelin.core!27
      594ff3fa
    • Carlos Ramos Carreño's avatar
      wcfs: tests: xbtree.py: Execute `zip` eagerly when we need list. · d014045b
      Carlos Ramos Carreño authored
      The builtin `zip` in Python 3 returns an iterator, not a list.
      Thus, one cannot directly use the `len` method on the object returned
      by `zip`, or we will have errors like the following one:
      
      ```python
      Traceback (most recent call last):
        File "/srv/slapgrid/slappart66/git/wendelin.core/wcfs/internal/xbtree/xbtreetest/treegen.py", line 617, in <module>
          main()
        File "/srv/slapgrid/slappart66/git/wendelin.core/wcfs/internal/xbtree/xbtreetest/treegen.py", line 613, in main
          cmd(argv)
        File "/srv/slapgrid/slappart66/venvs/wendelin.core/lib/python3.9/site-packages/decorator.py", line 232, in fun
          return caller(func, *(extras + args), **kw)
        File "/srv/slapgrid/slappart66/git/pygolang/golang/__init__.py", line 125, in _
          return f(*argv, **kw)
        File "/srv/slapgrid/slappart66/git/wendelin.core/wcfs/internal/xbtree/xbtreetest/treegen.py", line 589, in cmd_trees
          TreesSrv(zstor, r)
        File "/srv/slapgrid/slappart66/venvs/wendelin.core/lib/python3.9/site-packages/decorator.py", line 232, in fun
          return caller(func, *(extras + args), **kw)
        File "/srv/slapgrid/slappart66/git/pygolang/golang/__init__.py", line 125, in _
          return f(*argv, **kw)
        File "/srv/slapgrid/slappart66/git/wendelin.core/wcfs/internal/xbtree/xbtreetest/treegen.py", line 234, in TreesSrv
          treetxtPrev = zctx.ztreetxt(ztree)
        File "/srv/slapgrid/slappart66/venvs/wendelin.core/lib/python3.9/site-packages/decorator.py", line 232, in fun
          return caller(func, *(extras + args), **kw)
        File "/srv/slapgrid/slappart66/git/pygolang/golang/__init__.py", line 125, in _
          return f(*argv, **kw)
        File "/srv/slapgrid/slappart66/git/wendelin.core/wcfs/internal/xbtree/xbtreetest/treegen.py", line 536, in ztreetxt
          return zctx.TopoEncode(xbtree.StructureOf(ztree))
        File "/srv/slapgrid/slappart66/venvs/wendelin.core/lib/python3.9/site-packages/decorator.py", line 232, in fun
          return caller(func, *(extras + args), **kw)
        File "/srv/slapgrid/slappart66/git/pygolang/golang/__init__.py", line 125, in _
          return f(*argv, **kw)
        File "/srv/slapgrid/slappart66/git/wendelin.core/wcfs/internal/xbtree/xbtreetest/treegen.py", line 542, in TopoEncode
          return xbtree.TopoEncode(tree, zctx.vencode)
        File "/srv/slapgrid/slappart66/git/wendelin.core/wcfs/internal/xbtree.py", line 797, in TopoEncode
          for nodev in _walkBFS(tree):
        File "/srv/slapgrid/slappart66/git/wendelin.core/wcfs/internal/xbtree.py", line 701, in _walkBFS
          for level in __walkBFS(tree):
        File "/srv/slapgrid/slappart66/git/wendelin.core/wcfs/internal/xbtree.py", line 724, in __walkBFS
          assert len(rv) == len(rn.node.children)
      TypeError: object of type 'zip' has no len()
      ```
      
      Thus, we have to create a list from the result of `zip` before calling
      `len` on it.
      
      --------
      kirr:
      
      There were only two places where zip was used to build a list. All other
      places where zip is used - both in wcfs/xbtree and in other packages -
      are calling zip to iterate over zip result:
      
          (py39.venv) kirr@deca:~/src/wendelin/wendelin.core$ git grep -w zip
          bigarray/__init__.py:        for n, s in zip(self.shape, self.stridev):
          bigarray/__init__.py:        for n, s in zip(a.shape, a.strides):
          bigarray/array_zodb.py:BigArray_defaults = dict(zip(reversed(_.args), reversed(_.defaults)))
          wcfs/internal/xbtree.py:            for i, (klo, khi) in enumerate(zip(v[:-1], v[1:])): # (klo, khi) = [] of (k_i, k_{i+1})
          wcfs/internal/xbtree.py:                kvv = ['%s:%s' % (k,v) for (k,v) in zip(b.keyv, b.valuev)]
          wcfs/internal/xbtree.py:        for (j,i) in zip(jv, iv):
          wcfs/internal/xbtree.py:                    for (child, k) in zip(node.children[1:], node.keyv):
          wcfs/internal/xbtree.py:                    for (k,v) in zip(node.keyv, node.valuev):
          wcfs/internal/xbtree.py:            for (xlo, xhi) in zip(ksplitv[:-1], ksplitv[1:]): # (klo, s1), (s1, s2), ..., (sN, khi)
          wcfs/internal/xbtree.py:            for (xlo, xhi) in zip(ksplitv[:-1], ksplitv[1:]): # (klo, s1), (s1, s2), ..., (sN, khi)
          wcfs/internal/xbtree.py:                                    for (k,vtxt) in zip(node.keyv, vtxtv)])
          wcfs/internal/xbtree/xbtreetest/treegen.py:                    for (k,v) in zip(node.keyv, node.valuev):
          wcfs/internal/xbtree_test.py:    for (child, childOK) in zip(kids, children):
          wcfs/internal/xbtree_test.py:        for (i,(k,v)) in enumerate(zip(keys, values)):
      
          # handled in hereby patch
          wcfs/internal/xbtree.py:                rv = list(zip(v[:-1], v[1:]))  # (klo,k1), (k1,k2), ..., (kN,khi)
          wcfs/internal/xbtree.py:                rv = list(zip(v[:-1], v[1:]))  # (klo,k1), (k1,k2), ..., (kN,khi)
      
      /reviewed-by @kirr
      /reviewed-on nexedi/wendelin.core!27
      d014045b
    • Carlos Ramos Carreño's avatar
      bigarray: tests: Do not use `numpy.object`. · 84d3d775
      Carlos Ramos Carreño authored
      `numpy.object` was an alias for the builtin `object`, so we can use
      `object` instead:
      
      ```python
      _________________________ test_bigarray_noobject[tRAM] _________________________
      
      testbig = <bigarray.tests.test_basic.tRAM object at 0x7f6d114ead60>
      
          def test_bigarray_noobject(testbig):
              Zh = testbig.fopen()
      
              # NOTE str & unicode are fixed-size types - if size is not explicitly given
              # it will become S0 or U0
      >       obj_dtypev = [numpy.object, 'O', 'i4, O', [('x', 'i4'), ('y', 'i4, O')]]
      
      bigarray/tests/test_basic.py:110:
      _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
      
      attr = 'object'
      
          def __getattr__(attr):
              # Warn for expired attributes, and return a dummy function
              # that always raises an exception.
              import warnings
              import math
              try:
                  msg = __expired_functions__[attr]
              except KeyError:
                  pass
              else:
                  warnings.warn(msg, DeprecationWarning, stacklevel=2)
      
                  def _expired(*args, **kwds):
                      raise RuntimeError(msg)
      
                  return _expired
      
              # Emit warnings for deprecated attributes
              try:
                  val, msg = __deprecated_attrs__[attr]
              except KeyError:
                  pass
              else:
                  warnings.warn(msg, DeprecationWarning, stacklevel=2)
                  return val
      
              if attr in __future_scalars__:
                  # And future warnings for those that will change, but also give
                  # the AttributeError
                  warnings.warn(
                      f"In the future `np.{attr}` will be defined as the "
                      "corresponding NumPy scalar.", FutureWarning, stacklevel=2)
      
              if attr in __former_attrs__:
      >           raise AttributeError(__former_attrs__[attr])
      E           AttributeError: module 'numpy' has no attribute 'object'.
      E           `np.object` was a deprecated alias for the builtin `object`. To avoid this error in existing code, use `object` by itself. Doing this will not modify any behavior and is safe.
      E           The aliases was originally deprecated in NumPy 1.20; for more details and guidance see the original release note at:
      E               https://numpy.org/devdocs/release/1.20.0-notes.html#deprecations
      ```
      
      --------
      kirr:
      
      On py2:
      
          In [1]: import numpy
      
          In [2]: numpy.__version__
          Out[2]: '1.16.6'
      
          In [3]: numpy.object
          Out[3]: object
      
          In [4]: numpy.object is object
          Out[4]: True
      
      this change is, thus, indeed safe to make.
      
      /reviewed-by @kirr
      /reviewed-on nexedi/wendelin.core!27
      84d3d775
    • Carlos Ramos Carreño's avatar
      lib/zodb: tests: Do not import NEO globally. · b8a98631
      Carlos Ramos Carreño authored
      NEO is still not ported to Python 3.
      Importing NEO globally thus makes pytest tests fail during the
      assert-rewritting step:
      ```python
      ../../venvs/wendelin.core/lib/python3.9/site-packages/_pytest/assertion/rewrite.py:178: in exec_module
          exec(co, module.__dict__)
      lib/tests/test_zodb.py:36: in <module>
          from neo.client.Storage import Storage as NEOStorage
      ../neoppod/neo/client/__init__.py:52: in <module>
          from . import app # set up signal handlers early enough to do it in the main thread
      E     File "/srv/slapgrid/slappart66/git/neoppod/neo/client/app.py", line 356
      E       except NEOStorageReadRetry, e:
      E                                 ^
      E   SyntaxError: invalid syntax
      ```
      
      A MR adding enough support to not fail at import time is proposed in
      nexedi/neoppod!24 .
      However, that MR will not be reviewed until the vacation period is over.
      
      In the meantime, and as a previous step to make running NEO tests
      optional, the import has been moved inside the function loading NEO.
      Thus, only the tests that require NEO will fail.
      
      --------
      kirr:
      
      Add TODO to revert to import NEO globally after lab.nexedi.com/nexedi/neoppod/-/merge_requests/24 is landed.
      
      /reviewed-by @kirr
      /reviewed-on nexedi/wendelin.core!27
      b8a98631
    • Carlos Ramos Carreño's avatar
      setup: Install `ZEO[test]` when testing. · d640c701
      Carlos Ramos Carreño authored
      `ZEO[test]` should be installed when testing, so that `zope.testing` is
      installed.
      Otherwise, an import error may be raised when running the test if
      `zope.testing` has not been manually installed.
      
      --------
      kirr:
      
      Adjust tox.ini to no longer install zope.testing explicitly since we are
      now requesting ZEO[test] under our own tests extra, and tox.ini installs
      .[test] as the primary package.
      
      /reviewed-by @kirr
      /reviewed-on nexedi/wendelin.core!27
      d640c701
  5. 21 Jun, 2024 1 commit
    • Kirill Smelkov's avatar
      *: Do not use relative imports · 3846997b
      Kirill Smelkov authored
      Because of the way wendelin.core organizes its in-tree python importing
      redirector (see wendelin.py) it is possible to import the same module
      twice with python thinking it is importing two different modules. For
      example when installed in develop mode python resolves the following
      imports to the same bigfile/__init__.py
      
          import wendelin.bigfile
          import bigfile
      
      but tries to load that module twice and independently. Which leads to
      virtmem DSO, linked to from under bigfile/_bigfile extension, being
      initialized twice and complaining about that because only single gil
      hook should be requested to be installed:
      
          (py39.venv) kirr@deca:~/src/wendelin/wendelin.core$ python
          Python 3.9.19+ (heads/3.9:40d77b93672, Apr 12 2024, 06:40:05)
          [GCC 12.2.0] on linux
          Type "help", "copyright", "credits" or "license" for more information.
          >>> import wendelin.bigfile
          >>> import bigfile
          python: bigfile/virtmem.c:106: virt_lock_hookgil: Assertion `!(virtmem_gilhooks)' failed.
          Аварийный останов
      
      This problem was there from day 1, but it was not creating issues in
      practice because wendelin.core users do `import wendelin...` and there
      was also no problem with running pytest in the source tree.
      
      However with py39 and pytest8 we see that running pytest somehow started
      to unconditionally import things from under two namespaces which leads
      to inability to run tests even when instructing pytest to collect them
      via python-modules namespace instead of filesystem:
      
          (py39.venv) kirr@deca:~/src/wendelin/wendelin.core$ pytest -vsx --pyargs wendelin.bigfile.tests.test_basic
          ======================== test session starts ========================
          platform linux -- Python 3.9.19+, pytest-8.2.2, pluggy-1.5.0 -- /home/kirr/src/wendelin/venv/py39.venv/bin/python3.9
          cachedir: .pytest_cache
          rootdir: /home/kirr/src/wendelin/wendelin.core
          configfile: pyproject.toml
          collecting ... python3.9: bigfile/virtmem.c:106: virt_lock_hookgil: Assertion `!(virtmem_gilhooks)' failed.
          Fatal Python error: Aborted
      
          Current thread 0x00007fa172a60740 (most recent call first):
            File "<frozen importlib._bootstrap>", line 228 in _call_with_frames_removed
            File "<frozen importlib._bootstrap_external>", line 1173 in create_module
            File "<frozen importlib._bootstrap>", line 565 in module_from_spec
            File "<frozen importlib._bootstrap>", line 666 in _load_unlocked
            File "<frozen importlib._bootstrap>", line 986 in _find_and_load_unlocked
            File "<frozen importlib._bootstrap>", line 1007 in _find_and_load
            File "/home/kirr/src/wendelin/wendelin.core/bigfile/__init__.py", line 31 in <module>
            File "<frozen importlib._bootstrap>", line 228 in _call_with_frames_removed
            File "<frozen importlib._bootstrap_external>", line 850 in exec_module
            File "<frozen importlib._bootstrap>", line 680 in _load_unlocked
            File "<frozen importlib._bootstrap>", line 986 in _find_and_load_unlocked
            File "<frozen importlib._bootstrap>", line 1007 in _find_and_load
            File "<frozen importlib._bootstrap>", line 1030 in _gcd_import
            File "<frozen importlib._bootstrap>", line 228 in _call_with_frames_removed
            File "<frozen importlib._bootstrap>", line 972 in _find_and_load_unlocked
            File "<frozen importlib._bootstrap>", line 1007 in _find_and_load
            File "<frozen importlib._bootstrap>", line 1030 in _gcd_import
            File "<frozen importlib._bootstrap>", line 228 in _call_with_frames_removed
            File "<frozen importlib._bootstrap>", line 972 in _find_and_load_unlocked
            File "<frozen importlib._bootstrap>", line 1007 in _find_and_load
            File "<frozen importlib._bootstrap>", line 1030 in _gcd_import
            File "/home/kirr/local/py3.9/lib/python3.9/importlib/__init__.py", line 127 in import_module
            File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/_pytest/pathlib.py", line 591 in import_path
            File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/_pytest/python.py", line 492 in importtestmodule
            ...
            File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/_pytest/runner.py", line 567 in collect_one_node
            File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/_pytest/main.py", line 837 in _collect_one_node
            File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/_pytest/main.py", line 974 in genitems
            File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/_pytest/main.py", line 811 in perform_collect
            File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/_pytest/main.py", line 349 in pytest_collection
            ...
            File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/_pytest/config/__init__.py", line 178 in main
            File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/_pytest/config/__init__.py", line 206 in console_main
            File "/home/kirr/src/wendelin/venv/py39.venv/bin/pytest", line 8 in <module>
          Аварийный останов (образ памяти сброшен на диск)
      
      This happens because wendelin.bigfile is importing
      wendelin.bigfile._bigfile as `from ._bigfile import ...` which under
      pytest leads to importing both wendelin.bigfile._bigfile and
      bigfile._bigfile and further conflicting when setting up GIL hooks.
      
      -> Fix this issue by avoiding relative imports and always referring to
         wendelin.core modules with `wendelin.` prefix.
      
      The list of places where relative imports were used was small and found via
      
          $ git grep -w import |grep '\s\.'
          bigfile/__init__.py:from ._bigfile import BigFile, WRITEOUT_STORE, WRITEOUT_MARKSTORED, ram_reclaim
          wcfs/__init__.py:from .client._wcfs import \
      
      Everywhere else we were already importing things from under wendelin
      namespace via fully specified module path.
      
      After the fix both
      
          $ pytest -vsx --pyargs wendelin.bigfile.tests.test_basic
      
      and
      
          $ pytest -vsx bigfile/tests/test_basic.py
      
      start to work ok from inside the worktree.
      
      /reported-and-tested-by @vnmabus
      /reviewed-by @levin.zimmermann
      /reviewed-on nexedi/wendelin.core!26
      3846997b
  6. 07 Jun, 2024 1 commit
    • Carlos Ramos Carreño's avatar
      setup: Allow editable wheels. · 37cf1383
      Carlos Ramos Carreño authored
      When building an editable wheel it is not necessary that
      `build_packages` (or even `run`) is called before calling `get_outputs`
      (notice the following in
      https://setuptools.pypa.io/en/latest/userguide/extension.html#supporting-sdists-and-editable-installs-in-build-sub-commands :
      "Please note that custom sub-commands SHOULD NOT rely on `run()` being
      executed (or not) to provide correct return values for `get_outputs()`,
      `get_output_mapping()` or `get_source_files()`. The `get_*` methods
      should work independently of `run().").
      
      Our implementation relied in the call to `build_packages` to set the
      name of the synthetic init file.
      This commit uses a property of the object instead, to compute that name
      whenever it is necessary.
      With this change, it is now possible to make editable wheels.
      
      --------
      kirr:
      
      Without the fix `pip install -e` fails as follows on py3:
      
        Traceback (most recent call last):
          File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/setuptools/command/editable_wheel.py", line 155, in run
            self._create_wheel_file(bdist_wheel)
          File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/setuptools/command/editable_wheel.py", line 357, in _create_wheel_file
            files, mapping = self._run_build_commands(dist_name, unpacked, lib, tmp)
          File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/setuptools/command/editable_wheel.py", line 281, in _run_build_commands
            files, mapping = self._collect_build_outputs()
          File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/setuptools/command/editable_wheel.py", line 266, in _collect_build_outputs
            files.extend(cmd.get_outputs() or [])
          File "<string>", line 137, in get_outputs
          File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/setuptools/command/build_py.py", line 78, in __getattr__
            return orig.build_py.__getattr__(self, attr)
          File "/home/kirr/src/wendelin/venv/py39.venv/lib/python3.9/site-packages/setuptools/_distutils/cmd.py", line 107, in __getattr__
            raise AttributeError(attr)
        AttributeError: initfile
      
      /reviewed-by @kirr
      /reviewed-on nexedi/wendelin.core!25
      37cf1383
  7. 31 May, 2024 2 commits
  8. 03 Apr, 2024 1 commit
    • Levin Zimmermann's avatar
      bigfile/zodb: Make auto format the default · 99f262dd
      Levin Zimmermann authored
      If a user doesn't explicitly declare a ZBlk format, it can be assumed
      that this user wants to have the best ratio between consumed storage space
      and data access speed. Currently the best ratio between these two is
      provided by the new 'auto' (heuristic) format. In case of small appends this
      format helps reducing storage space, and in any other case it just
      behaves like ZBlk0 [1]. Therefore this default ensures a fast access speed [2],
      but also avoids a massive data growth in case of many small appends [3].
      
      [1] An exception to this is: in its current implementation a block
      behaves like ZBlk1 (slow access) in case it isn't fully filled up yet.
      
      [2] As this was stated as a reason why ZBlk1 as a default format was
      reverted in nexedi/wendelin.core@0b68f178.
      
      [3] This was perhaps the reason why ZBlk1 was set to be the default format
      in nexedi/wendelin.core@9ae42085. The massive
      storage space consumption can already be a problem with few array to
      which regularly small data is appended to, as it can easily happen with
      Wendelin development instances.
      
      /reviewed-by @kirr
      /reviewed-on nexedi/wendelin.core!20
      99f262dd