##// END OF EJS Templates
upstream » mercurial-mirror
RSS

Clone from https://www.mercurial-scm.org/repo/hg-all

merge: mark file gets as not thread safe (issue5933)...
merge: mark file gets as not thread safe (issue5933) In default installs, this has the effect of disabling the thread-based worker on Windows when manifesting files in the working directory. My measurements have shown that with revlog-based repositories, Mercurial spends a lot of CPU time in revlog code resolving file data. This ends up incurring a lot of context switching across threads and slows down `hg update` operations when going from an empty working directory to the tip of the repo. On mozilla-unified (246,351 files) on an i7-6700K (4+4 CPUs): before: 487s wall after: 360s wall (equivalent to worker.enabled=false) cpus=2: 379s wall Even with only 2 threads, the thread pool is still slower. The introduction of the thread-based worker (02b36e860e0b) states that it resulted in a "~50%" speedup for `hg sparse --enable-profile` and `hg sparse --disable-profile`. This disagrees with my measurement above. I theorize a few reasons for this: 1) Removal of files from the working directory is I/O - not CPU - bound and should benefit from a thread pool (unless I/O is insanely fast and the GIL release is near instantaneous). So tests like `hg sparse --enable-profile` may exercise deletion throughput and aren't good benchmarks for worker tasks that are CPU heavy. 2) The patch was authored by someone at Facebook. The results were likely measured against a repository using remotefilelog. And I believe that revision retrieval during working directory updates with remotefilelog will often use a remote store, thus being I/O and not CPU bound. This probably resulted in an overstated performance gain. Since there appears to be a need to enable the thread-based worker with some stores, I've made the flagging of file gets as thread safe configurable. I've made it experimental because I don't want to formalize a boolean flag for this option and because this attribute is best captured against the store implementation. But we don't have a proper store API for this yet. I'd rather cross this bridge later. It is possible there are revlog-based repositories that do benefit from a thread-based worker. I didn't do very comprehensive testing. If there are, we may want to devise a more proper algorithm for whether to use the thread-based worker, including possibly config options to limit the number of threads to use. But until I see evidence that justifies complexity, simplicity wins. Differential Revision: https://phab.mercurial-scm.org/D3963
Gregory Szorc - - Load All Authors

File last commit:

r37513:b1fb341d default
r38755:be498426 default
Show More
clang-format-ignorelist
88 lines | 4.0 KiB | text/plain | TextLexer
/ contrib / clang-format-ignorelist
History | Annotation | Raw |Copy content |Copy permalink
# Files that just need to be migrated to the formatter.
# Do not add new files here!
mercurial/cext/dirs.c
mercurial/cext/manifest.c
mercurial/cext/osutil.c
mercurial/cext/revlog.c
# Vendored code that we should never format:
contrib/python-zstandard/c-ext/bufferutil.c
contrib/python-zstandard/c-ext/compressiondict.c
contrib/python-zstandard/c-ext/compressionparams.c
contrib/python-zstandard/c-ext/compressionreader.c
contrib/python-zstandard/c-ext/compressionwriter.c
contrib/python-zstandard/c-ext/compressobj.c
contrib/python-zstandard/c-ext/compressor.c
contrib/python-zstandard/c-ext/compressoriterator.c
contrib/python-zstandard/c-ext/constants.c
contrib/python-zstandard/c-ext/decompressionreader.c
contrib/python-zstandard/c-ext/decompressionwriter.c
contrib/python-zstandard/c-ext/decompressobj.c
contrib/python-zstandard/c-ext/decompressor.c
contrib/python-zstandard/c-ext/decompressoriterator.c
contrib/python-zstandard/c-ext/frameparams.c
contrib/python-zstandard/c-ext/python-zstandard.h
contrib/python-zstandard/zstd.c
contrib/python-zstandard/zstd/common/bitstream.h
contrib/python-zstandard/zstd/common/compiler.h
contrib/python-zstandard/zstd/common/cpu.h
contrib/python-zstandard/zstd/common/entropy_common.c
contrib/python-zstandard/zstd/common/error_private.c
contrib/python-zstandard/zstd/common/error_private.h
contrib/python-zstandard/zstd/common/fse_decompress.c
contrib/python-zstandard/zstd/common/fse.h
contrib/python-zstandard/zstd/common/huf.h
contrib/python-zstandard/zstd/common/mem.h
contrib/python-zstandard/zstd/common/pool.c
contrib/python-zstandard/zstd/common/pool.h
contrib/python-zstandard/zstd/common/threading.c
contrib/python-zstandard/zstd/common/threading.h
contrib/python-zstandard/zstd/common/xxhash.c
contrib/python-zstandard/zstd/common/xxhash.h
contrib/python-zstandard/zstd/common/zstd_common.c
contrib/python-zstandard/zstd/common/zstd_errors.h
contrib/python-zstandard/zstd/common/zstd_internal.h
contrib/python-zstandard/zstd/compress/fse_compress.c
contrib/python-zstandard/zstd/compress/huf_compress.c
contrib/python-zstandard/zstd/compress/zstd_compress.c
contrib/python-zstandard/zstd/compress/zstd_compress_internal.h
contrib/python-zstandard/zstd/compress/zstd_double_fast.c
contrib/python-zstandard/zstd/compress/zstd_double_fast.h
contrib/python-zstandard/zstd/compress/zstd_fast.c
contrib/python-zstandard/zstd/compress/zstd_fast.h
contrib/python-zstandard/zstd/compress/zstd_lazy.c
contrib/python-zstandard/zstd/compress/zstd_lazy.h
contrib/python-zstandard/zstd/compress/zstd_ldm.c
contrib/python-zstandard/zstd/compress/zstd_ldm.h
contrib/python-zstandard/zstd/compress/zstdmt_compress.c
contrib/python-zstandard/zstd/compress/zstdmt_compress.h
contrib/python-zstandard/zstd/compress/zstd_opt.c
contrib/python-zstandard/zstd/compress/zstd_opt.h
contrib/python-zstandard/zstd/decompress/huf_decompress.c
contrib/python-zstandard/zstd/decompress/zstd_decompress.c
contrib/python-zstandard/zstd/deprecated/zbuff_common.c
contrib/python-zstandard/zstd/deprecated/zbuff_compress.c
contrib/python-zstandard/zstd/deprecated/zbuff_decompress.c
contrib/python-zstandard/zstd/deprecated/zbuff.h
contrib/python-zstandard/zstd/dictBuilder/cover.c
contrib/python-zstandard/zstd/dictBuilder/divsufsort.c
contrib/python-zstandard/zstd/dictBuilder/divsufsort.h
contrib/python-zstandard/zstd/dictBuilder/zdict.c
contrib/python-zstandard/zstd/dictBuilder/zdict.h
contrib/python-zstandard/zstd/zstd.h
hgext/fsmonitor/pywatchman/bser.c
mercurial/thirdparty/xdiff/xdiff.h
mercurial/thirdparty/xdiff/xdiffi.c
mercurial/thirdparty/xdiff/xdiffi.h
mercurial/thirdparty/xdiff/xemit.c
mercurial/thirdparty/xdiff/xemit.h
mercurial/thirdparty/xdiff/xhistogram.c
mercurial/thirdparty/xdiff/xinclude.h
mercurial/thirdparty/xdiff/xmacros.h
mercurial/thirdparty/xdiff/xmerge.c
mercurial/thirdparty/xdiff/xpatience.c
mercurial/thirdparty/xdiff/xprepare.c
mercurial/thirdparty/xdiff/xprepare.h
mercurial/thirdparty/xdiff/xtypes.h
mercurial/thirdparty/xdiff/xutils.c
mercurial/thirdparty/xdiff/xutils.h
mercurial/thirdparty/zope/interface/_zope_interface_coptimizations.c