From 21f4cd479ab416f83defc284c68966752705a48d Mon Sep 17 00:00:00 2001
From: pshu <stormslowly@gmail.com>
Date: Tue, 9 Jun 2026 14:30:11 +0800
Subject: [PATCH] ci: disable mimalloc purge delay for codspeed cpu simulation

Mimalloc delayed purging can call clock_gettime during CPU simulation
measurements, adding allocator timing noise to CodSpeed stage benchmarks.
Set MIMALLOC_PURGE_DELAY=-1 on the simulation run to keep that noise out
while leaving memory runs unchanged.
---
 .github/workflows/benchmark.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/workflows/benchmark.yml b/.github/workflows/benchmark.yml
index b5c3e647..e646e914 100644
--- a/.github/workflows/benchmark.yml
+++ b/.github/workflows/benchmark.yml
@@ -66,6 +66,7 @@ jobs:
         env:
           TMPDIR: ${{ runner.temp }}/codspeed-valgrind-tmp
           CODSPEED_EXPERIMENTAL_FAIR_SCHED: true
+          MIMALLOC_PURGE_DELAY: "-1"
         with:
           mode: simulation
           run: cargo codspeed run