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Date:   Wed, 1 Nov 2023 14:59:06 +0100
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Subject: Re: [RFC PATCH v4 0/9] slub: Delay freezing of CPU partial slabs
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To:     chengming.zhou@linux.dev, cl@linux.com, penberg@kernel.org,
        willy@infradead.org
Cc:     rientjes@google.com, iamjoonsoo.kim@lge.com,
        akpm@linux-foundation.org, roman.gushchin@linux.dev,
        42.hyeyoo@gmail.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        Chengming Zhou <zhouchengming@bytedance.com>
References: <20231031140741.79387-1-chengming.zhou@linux.dev>
From:   Vlastimil Babka <vbabka@suse.cz>
In-Reply-To: <20231031140741.79387-1-chengming.zhou@linux.dev>
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> 3. Testing
> ==========
> We just did some simple testing on a server with 128 CPUs (2 nodes) to
> compare performance for now.
> 
>  - perf bench sched messaging -g 5 -t -l 100000
>    baseline	RFC
>    7.042s	6.966s
>    7.022s	7.045s
>    7.054s	6.985s
> 
>  - stress-ng --rawpkt 128 --rawpkt-ops 100000000
>    baseline	RFC
>    2.42s	2.15s
>    2.45s	2.16s
>    2.44s	2.17s

Looks like these numbers are carried over from the first RFC. Could you
please retest with v4 as there were some bigger changes (i.e. getting
rid of acquire_slab()).

Otherwise I think v5 can drop "RFC" and will add it to slab tree after
the merge window and 6.7-rc1. Thanks!

> It shows above there is about 10% improvement on stress-ng rawpkt
> testcase, although no much improvement on perf sched bench testcase.
> 
> Thanks for any comment and code review!
> 
> Chengming Zhou (9):
>   slub: Reflow ___slab_alloc()
>   slub: Change get_partial() interfaces to return slab
>   slub: Keep track of whether slub is on the per-node partial list
>   slub: Prepare __slab_free() for unfrozen partial slab out of node
>     partial list
>   slub: Introduce freeze_slab()
>   slub: Delay freezing of partial slabs
>   slub: Optimize deactivate_slab()
>   slub: Rename all *unfreeze_partials* functions to *put_partials*
>   slub: Update frozen slabs documentations in the source
> 
>  mm/slub.c | 381 ++++++++++++++++++++++++++----------------------------
>  1 file changed, 180 insertions(+), 201 deletions(-)
>