On Thu, 17 Jan 2008 10:27:08 +0100 "Bart Van Assche" <bart.vanassche@xxxxxxxxx> wrote: > Hello, > > I have performed a test to compare the performance of SCST and STGT. > Apparently the SCST target implementation performed far better than > the STGT target implementation. This makes me wonder whether this is > due to the design of SCST or whether STGT's performance can be > improved to the level of SCST ? > > Test performed: read 2 GB of data in blocks of 1 MB from a target (hot > cache -- no disk reads were performed, all reads were from the cache). > Test command: time dd if=/dev/sde of=/dev/null bs=1M count=2000 > > STGT read SCST read > performance (MB/s) performance (MB/s) > Ethernet (1 Gb/s network) 77 89 > IPoIB (8 Gb/s network) 82 229 > SRP (8 Gb/s network) N/A 600 > iSER (8 Gb/s network) 80 N/A > > These results show that SCST uses the InfiniBand network very well > (effectivity of about 88% via SRP), but that the current STGT version > is unable to transfer data faster than 82 MB/s. Does this mean that > there is a severe bottleneck present in the current STGT > implementation ? I don't know about the details but Pete said that he can achieve more than 900MB/s read performance with tgt iSER target using ramdisk. http://www.mail-archive.com/stgt-devel@xxxxxxxxxxxxxxxx/msg00004.html - 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
