aligned_memory: use calloc to get zeroed memory #360
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@@ Coverage Diff @@
## main #360 +/- ##
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+ Coverage 90.21% 90.37% +0.15%
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Files 21 21
Lines 8312 8322 +10
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+ Hits 7499 7521 +22
+ Misses 813 801 -12
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Use calloc() instead of using malloc() + memset(). The former gets zeroed memory straight from the OS, avoids writing the memory twice (once to clear old content, once to zero it) and avoids actually paging in the whole new allocation due to memset.
Lichtso
approved these changes
Jul 22, 2022
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Use
calloc()instead of usingmalloc()+memset(). The former gets zeroed memory straight from the OS, avoids writing the memory twice (once to clear old content, once to zero it) and avoids actually paging in the whole new allocation due tomemset. See rust-lang/rust#54628.In practical terms, this halves memset usage while executing transactions, eliminating a frequent largeish memset in
CallFrames::new.Before:
After:
You can see that
memset_avx2_ermsis cut in half, andCallFrames::new()no longer shows up in profiles. (As for the other memsets, we'll probably be able to remove them when we implement unaligned memory mapping)