From: Andrea Arcangeli <aarcange@redhat.com>
To: Eric B Munson <emunson@mgebm.net>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
Michael J Wolf <mjwolf@us.ibm.com>
Subject: Re: [PATCH 0/5] fix up /proc/$pid/smaps to not split huge pages
Date: Tue, 15 Feb 2011 18:01:52 +0100 [thread overview]
Message-ID: <20110215170152.GF5935@random.random> (raw)
In-Reply-To: <20110215165510.GA2550@mgebm.net>
On Tue, Feb 15, 2011 at 11:55:10AM -0500, Eric B Munson wrote:
> I am noticing in smaps that KernelPageSize is wrong of areas
> that have been merged into THP. For instance:
>
> 7ff852a00000-7ff852c00000 rw-p 00000000 00:00 0
> Size: 2048 kB
> Rss: 2048 kB
> Pss: 2048 kB
> Shared_Clean: 0 kB
> Shared_Dirty: 0 kB
> Private_Clean: 0 kB
> Private_Dirty: 2048 kB
> Referenced: 2048 kB
> Anonymous: 2048 kB
> AnonHugePages: 2048 kB
> Swap: 0 kB
> KernelPageSize: 4 kB
> MMUPageSize: 4 kB
> Locked: 0 kB
>
> The entire mapping is contained in a THP but the
> KernelPageSize shows 4kb. For cases where the mapping might
> have mixed page sizes this may be okay, but for this
> particular mapping the 4kb page size is wrong.
I'm not sure this is a bug, if the mapping grows it may become 4096k
but the new pages may be 4k. There's no such thing as a
vma_mmu_pagesize in terms of hugepages because we support graceful
fallback and collapse/split on the fly without altering the vma. So I
think 4k is correct here.
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next prev parent reply other threads:[~2011-02-15 17:01 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-02-09 19:54 [PATCH 0/5] fix up /proc/$pid/smaps to not split huge pages Dave Hansen
2011-02-09 19:54 ` [PATCH 1/5] pagewalk: only split huge pages when necessary Dave Hansen
2011-02-10 11:11 ` Mel Gorman
2011-02-10 13:19 ` Andrea Arcangeli
2011-02-10 13:34 ` Mel Gorman
2011-02-09 19:54 ` [PATCH 2/5] break out smaps_pte_entry() from smaps_pte_range() Dave Hansen
2011-02-10 11:15 ` Mel Gorman
2011-02-09 19:54 ` [PATCH 3/5] pass pte size argument in to smaps_pte_entry() Dave Hansen
2011-02-10 11:16 ` Mel Gorman
2011-02-09 19:54 ` [PATCH 4/5] teach smaps_pte_range() about THP pmds Dave Hansen
2011-02-10 11:17 ` Mel Gorman
2011-02-10 18:08 ` Andrea Arcangeli
2011-02-10 19:32 ` Dave Hansen
2011-02-09 19:54 ` [PATCH 5/5] have smaps show transparent huge pages Dave Hansen
2011-02-10 11:20 ` Mel Gorman
2011-02-10 15:01 ` Dave Hansen
2011-02-10 15:09 ` Mel Gorman
2011-02-10 18:09 ` Andrea Arcangeli
2011-02-10 18:20 ` Dave Hansen
2011-02-10 18:39 ` Andrea Arcangeli
2011-02-09 21:24 ` [PATCH 0/5] fix up /proc/$pid/smaps to not split " Andrea Arcangeli
2011-02-20 21:54 ` David Rientjes
2011-02-15 16:55 ` Eric B Munson
2011-02-15 17:01 ` Andrea Arcangeli [this message]
2011-02-15 17:05 ` Dave Hansen
2011-02-15 18:00 ` Andrea Arcangeli
-- strict thread matches above, loose matches on Subject: below --
2011-02-22 1:53 Dave Hansen
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