[libc-commits] [libc] [libc] Default to a single threaded thread pool for GPU tests (PR #74486)

[Joseph Huber via libc-commits]

https://github.com/jhuber6 created https://github.com/llvm/llvm-project/pull/74486

Summary:
The GPU tests tend to fail when run massively in parallel. This is why
we use a CMake job pool to limit it to 1 in most cases. We should
default to the configuration that is most likely to work, that being a
single thread. There aren't enough GPU tests for this to be a massive
increase in test time on the bots, so we should default to what works
guaranteed.


>From e1493c06afde20f932cd88052809668a3af346d1 Mon Sep 17 00:00:00 2001
From: Joseph Huber <huberjn at outlook.com>
Date: Tue, 5 Dec 2023 09:21:31 -0600
Subject: [PATCH] [libc] Default to a single threaded thread pool for GPU tests

Summary:
The GPU tests tend to fail when run massively in parallel. This is why
we use a CMake job pool to limit it to 1 in most cases. We should
default to the configuration that is most likely to work, that being a
single thread. There aren't enough GPU tests for this to be a massive
increase in test time on the bots, so we should default to what works
guaranteed.
---
 libc/cmake/modules/prepare_libc_gpu_build.cmake | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libc/cmake/modules/prepare_libc_gpu_build.cmake b/libc/cmake/modules/prepare_libc_gpu_build.cmake
index 377bc4eeae8fc..f3ccbdc9eb15a 100644
--- a/libc/cmake/modules/prepare_libc_gpu_build.cmake
+++ b/libc/cmake/modules/prepare_libc_gpu_build.cmake
@@ -78,6 +78,9 @@ set(LIBC_GPU_TEST_JOBS "" CACHE STRING "Number of jobs to use for GPU tests")
 if(LIBC_GPU_TEST_JOBS)
   set_property(GLOBAL PROPERTY JOB_POOLS LIBC_GPU_TEST_POOL=${LIBC_GPU_TEST_JOBS})
   set(LIBC_HERMETIC_TEST_JOB_POOL JOB_POOL LIBC_GPU_TEST_POOL)
+else()
+  set_property(GLOBAL PROPERTY JOB_POOLS LIBC_GPU_TEST_POOL=1)
+  set(LIBC_HERMETIC_TEST_JOB_POOL JOB_POOL LIBC_GPU_TEST_POOL)
 endif()
 
 set(LIBC_GPU_TEST_ARCHITECTURE "" CACHE STRING "Architecture for the GPU tests")