neonvm-kernel: Add debug logs for kcompactd/offlining race #1400
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We are currently seeing a small base rate of a kernel bug where kcompactd is unable to handle a page fault during compaction. We suspect this *may* be due to a race condition between memory offlining and kcompactd, but it's hard to establish that concretely without more logs. So, let's add some debug logs indicating when kcompactd runs or offlining happens. ref https://neondb.slack.com/archives/C0807C9SSJ2/p1749652291036669
Omrigan
approved these changes
Jun 20, 2025
neonvm-kernel/patches/0005-Neon-mm-Add-debug-logs-for-kcompactd-offlining-race.patch
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We are currently seeing a small base rate of a kernel bug where kcompactd is unable to handle a page fault during compaction.
We suspect this may be due to a race condition between memory offlining and kcompactd, but it's hard to establish that concretely without more logs.
So, let's add some debug logs indicating when kcompactd runs or offlining happens.
ref https://neondb.slack.com/archives/C0807C9SSJ2/p1749652291036669