On Jan 30, 2008 11:56 AM, FUJITA Tomonori <tomof@xxxxxxx> wrote: > On Wed, 30 Jan 2008 09:38:04 +0100 > "Bart Van Assche" <bart.vanassche@xxxxxxxxx> 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 ratio 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. 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. Note: the InfiniBand kernel modules I used were those from the 2.6.22.9 kernel, not from the OFED distribution. Bart. - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
