[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20071026122155.45ce72e7.akpm@linux-foundation.org>
Date: Fri, 26 Oct 2007 12:21:55 -0700
From: Andrew Morton <akpm@...ux-foundation.org>
To: Ingo Molnar <mingo@...e.hu>
Cc: spamtrap@...bisoft.de, linux-kernel@...r.kernel.org,
a.p.zijlstra@...llo.nl, wfg@...l.ustc.edu.cn,
torvalds@...ux-foundation.org, riel@...hat.com
Subject: Re: 2.6.24-rc1: First impressions
On Fri, 26 Oct 2007 17:22:21 +0200
Ingo Molnar <mingo@...e.hu> wrote:
>
> * Martin Knoblauch <spamtrap@...bisoft.de> wrote:
>
> > Hi ,
> >
> > just to give some feedback on 2.6.24-rc1. For some time I am tracking
> > IO/writeback problems that hurt system responsiveness big-time. I
> > tested Peters stuff together with Fenguangs additions and it looked
> > promising. Therefore I was very happy to see Peters stuff going into
> > 2.6.24 and waited eagerly for rc1. In short, I am impressed. This
> > really looks good. IO throughput is great and I could not reproduce
> > the responsiveness problems so far.
> >
> > Below are a some numbers of my brute-force I/O tests that I can use
> > to bring responsiveness down. My platform is a HP/DL380g4, dual CPUs,
> > HT-enabled, 8 GB Memory, SmartaArray6i controller with 4x72GB SCSI
> > disks as RAID5 (battery protected writeback cahe enabled) and gigabit
> > networking (tg3). User space is 64-bit RHEL4.3
> >
> > I am basically doing copies using "dd" with 1MB blocksize. Local
> > Filesystem ist ext2 (noatime). IO-Scheduler is dealine, as it tends
> > to give best results. NFS3 Server is a Sun/T2000/Solaris10. The tests
> > are:
> >
> > dd1 - copy 16 GB from /dev/zero to local FS
> > dd1-dir - same, but using O_DIRECT for output
> > dd2/dd2-dir - copy 2x7.6 GB in parallel from /dev/zero to local FS
> > dd3/dd3-dir - copy 3x5.2 GB in parallel from /dev/zero lo local FS
> > net1 - copy 5.2 GB from NFS3 share to local FS
> > mix3 - copy 3x5.2 GB from /dev/zero to local disk and two NFS3 shares
> >
> > I did the numbers for 2.6.19.2, 2.6.22.6 and 2.6.24-rc1. All units
> > are MB/sec.
> >
> > test 2.6.19.2 2.6.22.6 2.6.24.-rc1
> > ----------------------------------------------------------------
> > dd1 28 50 96
> > dd1-dir 88 88 86
> > dd2 2x16.5 2x11 2x44.5
> > dd2-dir 2x44 2x44 2x43
> > dd3 3x9.8 3x8.7 3x30
> > dd3-dir 3x29.5 3x29.5 3x28.5
> > net1 30-33 50-55 37-52
> > mix3 17/32 25/50 96/35 (disk/combined-network)
>
> wow, really nice results!
Those changes seem suspiciously large to me. I wonder if there's less
physical IO happening during the timed run, and correspondingly more
afterwards.
> I think the MM should get out of deep-feature-freeze
> mode - there's tons of room to improve :-/
Kidding. We merge about 265 MM patches in 2.6.24-rc1:
482 files changed, 8071 insertions(+), 5142 deletions(-)
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists