[libcxx-commits] [PATCH] D126882: [libc++] Do not yield from __sp_mut::lock()

[Mark de Wever via Phabricator via libcxx-commits]

Mordante added inline comments.


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Comment at: libcxx/src/memory.cpp:141
 
-static constexpr std::size_t __sp_mut_count = 16;
+static constexpr std::size_t __sp_mut_count = 32;
 static constinit __libcpp_mutex_t mut_back[__sp_mut_count] =
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ldionne wrote:
> Mordante wrote:
> > Since you change this value it might be a good moment to document why 32 is "the right" value.
> Honestly, I just decided to double it to decrease contention a bit, but it wasn't done in any scientific kind of way.
Fair point. Since you looked at it with a performance engineer I hoped there was some additional info on this change.
If there isn't more info then it's fine by me too. 


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D126882/new/

https://reviews.llvm.org/D126882