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author | Julian Andres Klode <jak@debian.org> | 2018-12-26 12:39:56 +0100 |
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committer | Julian Andres Klode <jak@debian.org> | 2018-12-26 21:22:37 +0100 |
commit | 37ae749b20485b6c8237d5b5a08cfdd58a2364e1 (patch) | |
tree | 00d125414addc539da8dedf1a415a4ca29182669 /apt-pkg/aptconfiguration.h | |
parent | 68362f7996f4e72d73b40d61dc821610a1a4a148 (diff) |
cache hash: Use sse4.2 CRC32c on x86-64 where available
This is more than twice as fast as adler32, but could be made another
50% faster by calculating crcs for 8 byte blocks in "parallel" (without
data dependency) and then combining them. But that's complicated code.
Reference measurements for hashing the cache 100 times:
adler32=2.46s xxhash64=0.64 xxhash32=1.12
crc32c(this)=1.10 crc32c(opt)=0.44s
Diffstat (limited to 'apt-pkg/aptconfiguration.h')
0 files changed, 0 insertions, 0 deletions