bdiff: use Python memory allocator in fixws
Python has its own memory allocation APIs. For allocations
<= 512 bytes, it allocates memory from arenas. This means that
average small allocations don't call the system allocator, which
makes them faster. Also, arena allocations cut down on memory
fragmentation, which can matter for performance in long-running
processes.
Another advantage of using the Python memory allocator is that
allocations are tracked by Python. This is a bigger deal in
Python 3, as modern versions of Python have some decent built-in
tools for examining memory usage, leaks, etc.
This patch converts a trivial malloc() + free() in the bdiff code
to use the Python allocator APIs. Since the object being
operated on is a line, chances are it will use an arena. So,
this could have a net positive impact on performance (although
I didn't measure it).
#require test-repo
$ . "$TESTDIR/helpers-testrepo.sh"
$ import_checker="$TESTDIR"/../contrib/import-checker.py
$ cd "$TESTDIR"/..
There are a handful of cases here that require renaming a module so it
doesn't overlap with a stdlib module name. There are also some cycles
here that we should still endeavor to fix, and some cycles will be
hidden by deduplication algorithm in the cycle detector, so fixing
these may expose other cycles.
Known-bad files are excluded by -X as some of them would produce unstable
outputs, which should be fixed later.
$ hg locate 'set:**.py or grep(r"^#!.*?python")' \
> 'tests/**.t' \
> -X contrib/debugshell.py \
> -X contrib/python-zstandard/ \
> -X contrib/win32/hgwebdir_wsgi.py \
> -X doc/gendoc.py \
> -X doc/hgmanpage.py \
> -X i18n/posplit \
> -X tests/test-hgweb-auth.py \
> -X tests/hypothesishelpers.py \
> -X tests/test-ctxmanager.py \
> -X tests/test-lock.py \
> -X tests/test-verify-repo-operations.py \
> -X tests/test-hook.t \
> -X tests/test-import.t \
> -X tests/test-imports-checker.t \
> -X tests/test-commit-interactive.t \
> -X tests/test-contrib-check-code.t \
> -X tests/test-extension.t \
> -X tests/test-hghave.t \
> -X tests/test-hgweb-no-path-info.t \
> -X tests/test-hgweb-no-request-uri.t \
> -X tests/test-hgweb-non-interactive.t \
> | sed 's-\\-/-g' | python "$import_checker" -