Pierre-Yves David <pierre-yves.david@octobus.net> [Wed, 15 Jan 2020 15:48:09 +0100] rev 44313
nodemap: add a (python) index class for persistent nodemap testing
Using the persistent nodemap require a compeling performance boost and an
existing implementation. The benefit of the persistent nodemap for pure python
code is unclear and we don't have a C implementation for it. Yet we would like
to actually start testing it in more details and define an API for using that
persistent nodemap.
We introduce a new `devel` config option to use an index class dedicated to
Nodemap Testing. This feature is "pure" only because having using a pure-python
index with the `cext` policy proved more difficult than I would like.
There is nothing going on in that class for now, but the coming changeset will
change that.
Differential Revision: https://phab.mercurial-scm.org/D7840
Pierre-Yves David <pierre-yves.david@octobus.net> [Wed, 15 Jan 2020 15:47:59 +0100] rev 44312
nodemap: delete older raw data file when creating a new ones
When we write new full files, it replace an older one with a different name. We
add the associated cleanup for the older file to be removed after the
transaction.
We delete all file matching the expected pattern to give use extra chance to
delete orphan files we might have failed to delete earlier.
Note: eventually we won't rewrite all data for each transaction. This is coming
in later changesets.
Differential Revision: https://phab.mercurial-scm.org/D7839
Pierre-Yves David <pierre-yves.david@octobus.net> [Wed, 15 Jan 2020 15:47:50 +0100] rev 44311
nodemap: use an intermediate "docket" file to carry small metadata
This intermediate file will make mmapping, transaction and content validation
easier. (Most of this usefulness will arrive gradually in later changeset). In
particular it will become very useful to append new data are the end of raw file
instead of rewriting on the file on each transaction.
See in code comments for details.
Differential Revision: https://phab.mercurial-scm.org/D7838
Pierre-Yves David <pierre-yves.david@octobus.net> [Wed, 15 Jan 2020 15:47:40 +0100] rev 44310
nodemap: only use persistent nodemap for non-inlined revlog
Revlog are inlined while they are small (to avoid having too many file to deal
with). The persistent nodemap will only provides a significant boost for large
enough revlog index. So it does not make sens to add an extra file to store
nodemap for small revlog.
We could consider inclining the nodemap data inside the revlog itself, but the
benefit is unclear so let it be an adventure for another time.
Differential Revision: https://phab.mercurial-scm.org/D7837