fix: use GOMAXPROCS instead of NumCPU for child process thread counts#279
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joshfriend wants to merge 1 commit intomainfrom
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fix: use GOMAXPROCS instead of NumCPU for child process thread counts#279joshfriend wants to merge 1 commit intomainfrom
joshfriend wants to merge 1 commit intomainfrom
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runtime.NumCPU() returns the node's CPU count (e.g. 64 on m5d.16xlarge), ignoring the cgroup CPU limit. This causes zstd and git pack operations to spawn more threads than the CFS quota allows, resulting in constant CPU throttling despite low average utilization. Use runtime.GOMAXPROCS(0) which reflects the cgroup-aware effective CPU count, matching the container's actual CPU limit.
worstell
approved these changes
Apr 29, 2026
alecthomas
approved these changes
Apr 29, 2026
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runtime.NumCPU()returns the node's CPU count (e.g. 64 on m5d.16xlarge), ignoring the cgroup CPU limit. This causes zstd (-T64) and git pack operations to spawn more threads than the CFS quota allows, resulting in constant CPU throttling despite low average utilization.Uses
runtime.GOMAXPROCS(0)which reflects the cgroup-aware effective CPU count, matching the container's actual CPU limit.