Re: [PATCH v4 1/3] mm/slub: Introduce two counters for partial objects

From: Vlastimil Babka
Date: Thu Mar 18 2021 - 08:19:09 EST

On 3/17/21 8:54 AM, Xunlei Pang wrote:
> The node list_lock in count_partial() spends long time iterating
> in case of large amount of partial page lists, which can cause
> thunder herd effect to the list_lock contention.
> We have HSF RT(High-speed Service Framework Response-Time) monitors,
> the RT figures fluctuated randomly, then we deployed a tool detecting
> "irq off" and "preempt off" to dump the culprit's calltrace, capturing
> the list_lock cost nearly 100ms with irq off issued by "ss", this also
> caused network timeouts.

I forgot to ask, how does "ss" come into this? It displays network connections
AFAIK. Does it read any SLUB counters or slabinfo?