From: Rik van Riel <riel@redhat.com>
To: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Jens Axboe <jens.axboe@oracle.com>, Ingo Molnar <mingo@elte.hu>,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Chris Mason <chris.mason@oracle.com>,
Clemens Ladisch <clemens@ladisch.de>,
Olivier Galibert <galibert@pobox.com>,
Vivek Goyal <vgoyal@redhat.com>,
Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>,
Matt Mackall <mpm@selenic.com>, Nick Piggin <npiggin@suse.de>,
Linux Memory Management List <linux-mm@kvack.org>,
linux-fsdevel@vger.kernel.org,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 10/15] readahead: add /debug/readahead/stats
Date: Thu, 25 Feb 2010 17:40:17 -0500 [thread overview]
Message-ID: <4B86FC51.80903@redhat.com> (raw)
In-Reply-To: <20100224031055.024165020@intel.com>
On 02/23/2010 10:10 PM, Wu Fengguang wrote:
> Collect readahead stats when CONFIG_READAHEAD_STATS=y.
>
> This is enabled by default because the added overheads are trivial:
> two readahead_stats() calls per readahead.
>
> Example output:
> (taken from a fresh booted NFS-ROOT box with rsize=16k)
>
> $ cat /debug/readahead/stats
> pattern readahead eof_hit cache_hit io sync_io mmap_io size async_size io_size
> initial 524 216 26 498 498 18 7 4 4
> subsequent 181 80 1 130 13 60 25 25 24
> context 94 28 3 85 64 8 7 2 5
> thrash 0 0 0 0 0 0 0 0 0
> around 162 121 33 162 162 162 60 0 21
> fadvise 0 0 0 0 0 0 0 0 0
> random 137 0 0 137 137 0 1 0 1
> all 1098 445 63 1012 874 0 17 6 9
>
> The two most important columns are
> - io number of readahead IO
> - io_size average readahead IO size
>
> CC: Ingo Molnar<mingo@elte.hu>
> CC: Jens Axboe<jens.axboe@oracle.com>
> CC: Peter Zijlstra<a.p.zijlstra@chello.nl>
> Signed-off-by: Wu Fengguang<fengguang.wu@intel.com>
Acked-by: Rik van Riel <riel@redhat.com>
WARNING: multiple messages have this Message-ID (diff)
From: Rik van Riel <riel@redhat.com>
To: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Jens Axboe <jens.axboe@oracle.com>, Ingo Molnar <mingo@elte.hu>,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Chris Mason <chris.mason@oracle.com>,
Clemens Ladisch <clemens@ladisch.de>,
Olivier Galibert <galibert@pobox.com>,
Vivek Goyal <vgoyal@redhat.com>,
Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>,
Matt Mackall <mpm@selenic.com>, Nick Piggin <npiggin@suse.de>,
Linux Memory Management List <linux-mm@kvack.org>,
linux-fsdevel@vger.kernel.org,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 10/15] readahead: add /debug/readahead/stats
Date: Thu, 25 Feb 2010 17:40:17 -0500 [thread overview]
Message-ID: <4B86FC51.80903@redhat.com> (raw)
In-Reply-To: <20100224031055.024165020@intel.com>
On 02/23/2010 10:10 PM, Wu Fengguang wrote:
> Collect readahead stats when CONFIG_READAHEAD_STATS=y.
>
> This is enabled by default because the added overheads are trivial:
> two readahead_stats() calls per readahead.
>
> Example output:
> (taken from a fresh booted NFS-ROOT box with rsize=16k)
>
> $ cat /debug/readahead/stats
> pattern readahead eof_hit cache_hit io sync_io mmap_io size async_size io_size
> initial 524 216 26 498 498 18 7 4 4
> subsequent 181 80 1 130 13 60 25 25 24
> context 94 28 3 85 64 8 7 2 5
> thrash 0 0 0 0 0 0 0 0 0
> around 162 121 33 162 162 162 60 0 21
> fadvise 0 0 0 0 0 0 0 0 0
> random 137 0 0 137 137 0 1 0 1
> all 1098 445 63 1012 874 0 17 6 9
>
> The two most important columns are
> - io number of readahead IO
> - io_size average readahead IO size
>
> CC: Ingo Molnar<mingo@elte.hu>
> CC: Jens Axboe<jens.axboe@oracle.com>
> CC: Peter Zijlstra<a.p.zijlstra@chello.nl>
> Signed-off-by: Wu Fengguang<fengguang.wu@intel.com>
Acked-by: Rik van Riel <riel@redhat.com>
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2010-02-25 22:41 UTC|newest]
Thread overview: 94+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-02-24 3:10 [PATCH 00/15] 512K readahead size with thrashing safe readahead v2 Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` [PATCH 01/15] readahead: limit readahead size for small devices Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 3:11 ` Rik van Riel
2010-02-25 3:11 ` Rik van Riel
2010-02-24 3:10 ` [PATCH 02/15] readahead: retain inactive lru pages to be accessed soon Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 3:17 ` Rik van Riel
2010-02-25 3:17 ` Rik van Riel
2010-02-25 12:27 ` Wu Fengguang
2010-02-25 12:27 ` Wu Fengguang
2010-02-24 3:10 ` [PATCH 03/15] readahead: bump up the default readahead size Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 4:02 ` Rik van Riel
2010-02-25 4:02 ` Rik van Riel
2010-02-24 3:10 ` [PATCH 04/15] readahead: make default readahead size a kernel parameter Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 14:59 ` Rik van Riel
2010-02-25 14:59 ` Rik van Riel
2010-02-24 3:10 ` [PATCH 05/15] readahead: limit readahead size for small memory systems Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 15:00 ` Rik van Riel
2010-02-25 15:00 ` Rik van Riel
2010-02-25 15:25 ` Christian Ehrhardt
2010-02-25 15:25 ` Christian Ehrhardt
2010-02-25 15:25 ` Christian Ehrhardt
2010-02-26 2:29 ` Wu Fengguang
2010-02-26 2:29 ` Wu Fengguang
2010-02-26 2:48 ` [PATCH] readahead: add notes on readahead size Wu Fengguang
2010-02-26 2:48 ` Wu Fengguang
2010-02-26 14:17 ` Vivek Goyal
2010-02-26 14:17 ` Vivek Goyal
2010-02-26 7:23 ` [PATCH 05/15] readahead: limit readahead size for small memory systems Christian Ehrhardt
2010-02-26 7:23 ` Christian Ehrhardt
2010-02-26 7:23 ` Christian Ehrhardt
2010-02-26 7:38 ` Wu Fengguang
2010-02-26 7:38 ` Wu Fengguang
2010-02-24 3:10 ` [PATCH 06/15] readahead: replace ra->mmap_miss with ra->ra_flags Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 15:52 ` Rik van Riel
2010-02-25 15:52 ` Rik van Riel
2010-02-24 3:10 ` [PATCH 07/15] readahead: thrashing safe context readahead Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 16:24 ` Rik van Riel
2010-02-25 16:24 ` Rik van Riel
2010-02-24 3:10 ` [PATCH 08/15] readahead: record readahead patterns Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 22:37 ` Rik van Riel
2010-02-25 22:37 ` Rik van Riel
2010-02-24 3:10 ` [PATCH 09/15] readahead: add tracing event Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 22:38 ` Rik van Riel
2010-02-25 22:38 ` Rik van Riel
2010-02-24 3:10 ` [PATCH 10/15] readahead: add /debug/readahead/stats Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 22:40 ` Rik van Riel [this message]
2010-02-25 22:40 ` Rik van Riel
2010-02-24 3:10 ` [PATCH 11/15] readahead: dont do start-of-file readahead after lseek() Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 22:42 ` Rik van Riel
2010-02-25 22:42 ` Rik van Riel
2010-02-24 3:10 ` [PATCH 12/15] radixtree: introduce radix_tree_lookup_leaf_node() Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 23:13 ` Rik van Riel
2010-02-25 23:13 ` Rik van Riel
2010-02-24 3:10 ` [PATCH 13/15] radixtree: speed up the search for hole Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 23:37 ` Rik van Riel
2010-02-25 23:37 ` Rik van Riel
2010-02-24 3:10 ` [PATCH 14/15] readahead: reduce MMAP_LOTSAMISS for mmap read-around Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-25 23:42 ` Rik van Riel
2010-02-25 23:42 ` Rik van Riel
2010-02-24 3:10 ` [PATCH 15/15] readahead: pagecache context based " Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-24 3:10 ` Wu Fengguang
2010-02-26 1:33 ` Rik van Riel
2010-02-26 1:33 ` Rik van Riel
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4B86FC51.80903@redhat.com \
--to=riel@redhat.com \
--cc=a.p.zijlstra@chello.nl \
--cc=akpm@linux-foundation.org \
--cc=chris.mason@oracle.com \
--cc=clemens@ladisch.de \
--cc=ehrhardt@linux.vnet.ibm.com \
--cc=fengguang.wu@intel.com \
--cc=galibert@pobox.com \
--cc=jens.axboe@oracle.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mingo@elte.hu \
--cc=mpm@selenic.com \
--cc=npiggin@suse.de \
--cc=vgoyal@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.