fix(cgroup): avoid early return when cpu.pressure file is missing#275
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orestisfl merged 4 commits intoelastic:mainfrom Jan 16, 2026
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When cpu.pressure file doesn't exist, the code was returning early, skipping the remaining CPU stats retrieval. Now it clears the error and continues execution to properly fetch all available stats.
AndersonQ
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Dec 12, 2025
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AndersonQ
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I run the test you added on main and it passes. I believe a better test would be to have a mock cpu.stat file. Then you can call CPUSubsystem.Get point to the folder with this file and assert it retruns the data of the file even though the cpu.pressure isn't there.
AndersonQ
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Jan 16, 2026
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What does this PR do?
Fixes a bug in the cgroup v2 CPU subsystem where the
Getmethod was returning early when thecpu.pressurefile doesn't exist.The change replaces
return nilwitherr = nil, allowing the function to continue execution and fetch the remaining CPU stats (usage, system time, etc.) even when pressure stats are unavailable.Also adds a new test
TestGetCPUEmptythat verifies the CPU subsystem correctly handles empty directories without errors.Why is it important?
On systems where
cpu.pressureis not available, the previous code would silently return without populating any CPU statistics. This meant that valid CPU metrics like usage and system time were being lost even though they were available in other files in the cgroup path.PSI can be disabled for linux in a number of ways:
CONFIG_PSIininit/Kconfig:CONFIG_PSI_DEFAULT_DISABLED=y, PSI is off unlesspsi=1is passed.cgroup_disable=pressure:Checklist
[ ] I have added an entry inCHANGELOG.mdRelated issues