From 7bee94b5c9142e17e22851530464a5f3f770c2c7 Mon Sep 17 00:00:00 2001 From: Thomas Lively Date: Tue, 27 Oct 2026 16:54:51 -0700 Subject: [PATCH 1/2] [Fuzzer] Update BINARYEN_CORES comment Explain that we are limiting the number of cores because the overhead from thread pool initialization and synchronization can be high when running on small modules. --- scripts/fuzz_opt.py | 3 +++ 1 file changed, 3 insertions(+) diff --git a/scripts/fuzz_opt.py b/scripts/fuzz_opt.py index dc9b9eb12f6..9b5b01719aa 100755 --- a/scripts/fuzz_opt.py +++ b/scripts/fuzz_opt.py @@ -51,6 +51,9 @@ # Limit default thread pool size per subprocess so parallel passes are still # exercised without spawning a thread per hardware core on every invocation. +# On machines with lots of cores, the overhead of setting up a full-sized +# thread pool and synchonization around funtion-parallel passes can be +# significant when running on the fuzzer's relatively small modules. os.environ.setdefault('BINARYEN_CORES', '4') # parameters From dd22ddf9510c98f672a73248220d34f054133e31 Mon Sep 17 00:00:00 2001 From: Thomas Lively Date: Tue, 27 Oct 2026 16:58:02 -0700 Subject: [PATCH 2/2] Update scripts/fuzz_opt.py Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com> --- scripts/fuzz_opt.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/fuzz_opt.py b/scripts/fuzz_opt.py index 9b5b01719aa..692d0c0746e 100755 --- a/scripts/fuzz_opt.py +++ b/scripts/fuzz_opt.py @@ -52,7 +52,7 @@ # Limit default thread pool size per subprocess so parallel passes are still # exercised without spawning a thread per hardware core on every invocation. # On machines with lots of cores, the overhead of setting up a full-sized -# thread pool and synchonization around funtion-parallel passes can be +# thread pool and synchronization around function-parallel passes can be # significant when running on the fuzzer's relatively small modules. os.environ.setdefault('BINARYEN_CORES', '4')