| commit | 2cfc70f0de7c8902791d3b23a92d6462b9e11d72 | [log] [tgz] |
|---|---|---|
| author | Jeff Hostetler <jeffhost@microsoft.com> | Thu Feb 09 23:27:49 2017 +0100 |
| committer | Junio C Hamano <gitster@pobox.com> | Thu Feb 09 15:40:06 2017 -0800 |
| tree | 8f16a18b996d5b79311e3326ce467f05c20b8870 | |
| parent | 3b9e3c2cede15057af3ff8076c45ad5f33829436 [diff] |
mingw: use OpenSSL's SHA-1 routines Use OpenSSL's SHA-1 routines rather than builtin block-sha1 routines. This improves performance on SHA1 operations on Intel processors. OpenSSL 1.0.2 has made considerable performance improvements and support the Intel hardware acceleration features. See: https://software.intel.com/en-us/articles/improving-openssl-performance https://software.intel.com/en-us/articles/intel-sha-extensions To test this I added/staged a single file in a gigantic repository having a 450MB index file. The code in read-cache.c verifies the header SHA as it reads the index and computes a new header SHA as it writes out the new index. Therefore, in this test the SHA code must process 900MB of data. Testing was done on an Intel I7-4770 CPU @ 3.40GHz (Intel64, Family 6, Model 60) CPU. The block-sha1 version averaged 5.27 seconds. The OpenSSL version averaged 4.50 seconds. ================================================================ $ echo xxx >> project.mk $ time /e/blk_sha/bin/git.exe add project.mk real 0m5.207s user 0m0.000s sys 0m0.250s $ echo xxx >> project.mk $ time /e/blk_sha/bin/git.exe add project.mk real 0m5.362s user 0m0.015s sys 0m0.234s $ echo xxx >> project.mk $ time /e/blk_sha/bin/git.exe add project.mk real 0m5.300s user 0m0.016s sys 0m0.250s $ echo xxx >> project.mk $ time /e/blk_sha/bin/git.exe add project.mk real 0m5.216s user 0m0.000s sys 0m0.250s ================================================================ $ echo xxx >> project.mk $ time /e/openssl/bin/git.exe add project.mk real 0m4.431s user 0m0.000s sys 0m0.250s $ echo xxx >> project.mk $ time /e/openssl/bin/git.exe add project.mk real 0m4.478s user 0m0.000s sys 0m0.265s $ echo xxx >> project.mk $ time /e/openssl/bin/git.exe add project.mk real 0m4.690s user 0m0.000s sys 0m0.250s $ echo xxx >> project.mk $ time /e/openssl/bin/git.exe add project.mk real 0m4.420s user 0m0.000s sys 0m0.234s ================================================================ Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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