From: Eric Dumazet <eric.dumazet@gmail.com>
To: Matthew Wilcox <willy@infradead.org>,
Alexander Duyck <alexander.duyck@gmail.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>,
linux-mm@vger.kernel.org, Netdev <netdev@vger.kernel.org>,
Matthew Wilcox <mawilcox@microsoft.com>
Subject: Re: [RFC 2/2] page_frag_cache: Store metadata in struct page
Date: Fri, 16 Mar 2018 14:32:22 -0700 [thread overview]
Message-ID: <8e8c5cfa-ae76-e672-3da1-818b5df4448b@gmail.com> (raw)
In-Reply-To: <20180316210500.GH27498@bombadil.infradead.org>
On 03/16/2018 02:05 PM, Matthew Wilcox wrote:
>
> Obviously if the problem turns out to be the cacheline thrashing rather
> than the call to page_to_virt, then this is pointless to test.
>
>> I won't be able to test the patches until next week, but I expect I
>> will probably see a noticeable regression when performing a small
>> packet routing test.
>
> I really appreciate you being willing to try this for me. I need to
> get myself a dual-socket machine to test things like this.
>
It seems my prior mail/answer was lost.
Issue is cacheline thrashing indeed, particularly on PowerPC (64 KB pages)
next prev parent reply other threads:[~2018-03-16 21:32 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-15 19:53 [RFC 0/2] Shrink page_frag_cache Matthew Wilcox
2018-03-15 19:53 ` [RFC 1/2] mm: Use page->mapping to indicate pfmemalloc Matthew Wilcox
2018-03-15 19:53 ` [RFC 2/2] page_frag_cache: Store metadata in struct page Matthew Wilcox
2018-03-15 21:03 ` Eric Dumazet
2018-03-15 21:26 ` Alexander Duyck
2018-03-16 21:05 ` Matthew Wilcox
2018-03-16 21:32 ` Eric Dumazet [this message]
2018-03-19 8:27 ` Jesper Dangaard Brouer
2018-03-17 20:54 ` David Miller
2018-03-17 2:17 ` [page_frag_cache] 47b0eaa4b5: BUG:unable_to_handle_kernel kernel test robot
2018-03-20 20:47 ` [RFC 2/2] page_frag_cache: Store metadata in struct page Alexander Duyck
2018-03-15 20:02 ` [RFC 0/2] Shrink page_frag_cache Alexander Duyck
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