Yes, using open-iscsi with tgt as the target side. I used fio with the following job file. I only used 1 job (thread) because I want to see the max that a single job can read at a time. Even by maximizing the MaxXmitDataSegmentLength and MaxRecvDataSegmentLength, I dont see much difference.
[default] rw=randread size=20g bs=16m ioengine=libaio direct=1 numjobs=1 filename=/dev/sdb runtime=600 write_bw_log=iscsiread Then I ran fio as follows: $ fio iscsi.job On Friday, August 22, 2014 5:00:33 PM UTC-4, Mike Christie wrote: > > Are you using linux for the initiator? If so, what is the throughput you > get from just using this open-iscsi initiator connected to tgt with a ram > disk? > > I just installed RBD here for work, so let me check it out. What io tool > are using and if it is something like fio could you post the arguments you > used to run it? > > > On Aug 21, 2014, at 4:10 PM, Wyllys Ingersoll <[email protected] > <javascript:>> wrote: > > > Im looking for suggestions about maximizing performance when using an RBD > backend (Ceph) over a 10GB Ethernet link. In my testing, I see the read > throughput max out at about 100Mbyte/second for just about any block sizes > above 4K (below 4K it becomes horribly slow) and write operations are about > 40Mbyte/second. > > Using librados directly to read from the same backend pool/image yields > much higher numbers, so the issue seems to be in the iscsi/bs_rbd backend. > Regardless of the data sizes being read, the max thruput I am seeing is > about 80% slower than using librados directly. > > Any suggestions would be much appreciated. > > thanks, > Wyllys > > > -- > You received this message because you are subscribed to the Google Groups > "open-iscsi" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] <javascript:>. > To post to this group, send email to [email protected] > <javascript:>. > Visit this group at http://groups.google.com/group/open-iscsi. > For more options, visit https://groups.google.com/d/optout. > > > -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/open-iscsi. For more options, visit https://groups.google.com/d/optout.
