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

[Xunlei Pang]

On 3/18/21 8:18 PM, Vlastimil Babka wrote:
> 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?
> 

ss may access /proc/slabinfo to acquire network related slab statistics.