From: Matthew Wilcox <willy@infradead.org>
To: Yafang Shao <laoar.shao@gmail.com>
Cc: David Rientjes <rientjes@google.com>,
Andrew Morton <akpm@linux-foundation.org>,
"Liam R. Howlett" <Liam.Howlett@oracle.com>,
Suren Baghdasaryan <surenb@google.com>,
Christoph Lameter <cl@linux.com>,
"Paul E. McKenney" <paulmck@kernel.org>,
Tejun Heo <tj@kernel.org>, Johannes Weiner <hannes@cmpxchg.org>,
Davidlohr Bueso <dave@stgolabs.net>,
Namhyung Kim <namhyung@google.com>,
linux-mm@kvack.org
Subject: Re: MM global locks as core counts quadruple
Date: Fri, 21 Jun 2024 03:54:31 +0100 [thread overview]
Message-ID: <ZnTrZ9mcAIRodnjx@casper.infradead.org> (raw)
In-Reply-To: <CALOAHbBTTs=4o=DsNL5f+dvt3fEwABTFMF25japrGL_FEzWSPA@mail.gmail.com>
On Fri, Jun 21, 2024 at 10:46:21AM +0800, Yafang Shao wrote:
> > This is only looking at fleet data for global static locks, not locks like
> > zone->lock that get dynamically allocated.
>
> We have encountered latency spikes caused by the zone->lock. Do we
> have any plans to eliminate this lock, such as implementing a lockless
> buddy list? I believe this could be a viable solution.
Lockless how? I see three operations being performed on the buddy list:
- Add to end (freeing)
- Remove from end (allocation)
- Remove from middle (buddy was freed, needs to be coalesced)
I don't see how we can handle this locklessly.
I think a more productive solution to contention on the LRU lock is to
increase the number of zones. I don't think it's helpful to have a
1TB zone of memory. Maybe we should limit each zone to 16GB or so.
That means we'd need to increase the number of zones we support, but
I think that's doable.
next prev parent reply other threads:[~2024-06-21 2:54 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-06-21 0:35 David Rientjes
2024-06-21 2:01 ` Matthew Wilcox
2024-06-21 2:46 ` Yafang Shao
2024-06-21 2:54 ` Matthew Wilcox [this message]
2024-06-26 19:38 ` Karim Manaouil
2024-06-27 5:36 ` Christoph Lameter (Ampere)
2024-06-21 19:10 ` Tejun Heo
2024-06-21 21:37 ` Namhyung Kim
2024-06-23 17:59 ` Tejun Heo
2024-06-24 21:44 ` David Rientjes
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