Messages in this thread | | | Date | Mon, 28 Oct 2019 17:27:00 -0700 (PDT) | From | David Rientjes <> | Subject | Re: [PATCH] mm: rate-limit allocation failure warnings more aggressively |
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On Mon, 28 Oct 2019, Johannes Weiner wrote:
> While investigating a bug related to higher atomic allocation > failures, we noticed the failure warnings positively drowning the > console, and in our case trigger lockup warnings because of a serial > console too slow to handle all that output. > > But even if we had a faster console, it's unclear what additional > information the current level of repetition provides. > > Allocation failures happen for three reasons: The machine is OOM, the > VM is failing to handle reasonable requests, or somebody is making > unreasonable requests (and didn't acknowledge their opportunism with > __GFP_NOWARN). Having the memory dump, a callstack, and the ratelimit > stats on skipped failure warnings should provide enough information to > let users/admins/developers know whether something is wrong and point > them in the right direction for debugging, bpftracing etc. > > Limit allocation failure warnings to 1 spew every ten seconds. > > Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: David Rientjes <rientjes@google.com>
It feels like the vmalloc warnings should be treated with their own ratelimit (pass a struct ratelimit_state * to warn_alloc()) but that's outside the scope of this particular change.
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