On 09/04/2009 06:54 AM, Angel L. Mateo wrote: > Hello everyone, > > I am introducing myself to iSCSI world, so maybe these are newbie > questions. I'm sorry. > > My first test has been to create a LUN (in a celerra file server) and > export it with iscsi. I have mounted this lun in a debian server > (lenny), created a file system, and mounted it. The problem I have is > that performance is poor than in a NFS FS (with NFS I get ~50MB/s and > with iSCSI I get ~10MB/s). I am mounting NFS and iSCSI filesystem over a > bonding (active/pasive) of two gigabit cards. I am using tcp transport > for iSCSI.
Can you try different IO schedulers echo noop > /sys/block/sdXYZ/queue/scheduler And for your IO test what are you using and what IO sizes are used? For a good throughput you want lots of IO (around the queue depth of the target which is probably around 128 or 256) and larger IOs (around 64 or 128K). > > Another question related with this, is that one of my cards is a > Broadcom NetXtremm II BMC5708S wich supports iSCSI. Although some man > pages talk about a bnx2i transport, I haven't found any kernel module > for this. Could I use this transport? How? Should it improves > performance? > You cannot use this transport with the upstream open-iscsi tools. The 2.6.31 kernel will have a bnx2i driver for that card, but you will still need a special broadcom daemon to use the offload capabilites of the card. Broadcom and other offload guys like Chelsio are working on merging a common daemon/lib into the open-iscsi package right now. I will let the broadcom guys talk about perf more because I do not have any numbers handy. From my testing I have seen it performs well with smaller IOs (less than 32K) and iscsi_tcp does not. With larger IOs and lots of them the throughput seems to the be same (at least with a 1 gig network), but the braodcom cpu usage is much less. iscsi_tcp has a xmit thread which can take up almost 100% of the cpu at times, but broadcom does not have that thread since it does the same operations in hardware. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "open-iscsi" group. To post to this group, send email to open-iscsi@googlegroups.com To unsubscribe from this group, send email to open-iscsi+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/open-iscsi -~----------~----~----~----~------~----~------~--~---
