lkml.org 
[lkml]   [2008]   [Jan]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    SubjectRe: Integration of SCST in the mainstream Linux kernel
    From
    On Wed, 30 Jan 2008 14:10:47 +0100
    "Bart Van Assche" <bart.vanassche@gmail.com> wrote:

    > On Jan 30, 2008 11:56 AM, FUJITA Tomonori <tomof@acm.org> wrote:
    > > On Wed, 30 Jan 2008 09:38:04 +0100
    > > "Bart Van Assche" <bart.vanassche@gmail.com> wrote:
    > > >
    > > > Please specify which parameters you are referring to. As you know I
    > >
    > > Sorry, I can't say. I don't know much about iSER. But seems that Pete
    > > and Robin can get the better I/O performance - line speed ratiwo with
    > > STGT.
    >
    > Robin Humble was using a DDR InfiniBand network, while my tests were
    > performed with an SDR InfiniBand network. Robin's results can't be
    > directly compared to my results.

    I know that you use different hardware. I used 'ratio' word.


    BTW, you said the performance difference of dio READ is 38% but I
    think it's 27.3 %, though it's still large.


    > Pete Wyckoff's results
    > (http://www.osc.edu/~pw/papers/wyckoff-iser-snapi07-talk.pdf) are hard
    > to interpret. I have asked Pete which of the numbers in his test can
    > be compared with what I measured, but Pete did not reply.
    >
    > > The version of OpenIB might matters too. For example, Pete said that
    > > STGT reads loses about 100 MB/s for some transfer sizes for some
    > > transfer sizes due to the OpenIB version difference or other unclear
    > > reasons.
    > >
    > > http://article.gmane.org/gmane.linux.iscsi.tgt.devel/135
    >
    > Pete wrote about a degradation from 600 MB/s to 500 MB/s for reads
    > with STGT+iSER. In my tests I measured 589 MB/s for reads (direct
    > I/O), which matches with the better result obtained by Pete.

    I don't know he used the same benchmark software so I don't think that
    we can compare them.

    All I tried to say is the OFED version might has big effect on the
    performance. So you might need to find the best one.


    > Note: the InfiniBand kernel modules I used were those from the
    > 2.6.22.9 kernel, not from the OFED distribution.

    I'm talking about a target machine (I think that Pete was also talking
    about OFED on his target machine). STGT uses OFED libraries, I think.


    \
     
     \ /
      Last update: 2008-01-30 14:57    [W:0.023 / U:122.180 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site