On 09/08/2011 09:23 PM, Mike Christie wrote: > On 09/08/2011 04:36 PM, Mike Christie wrote: >> On 09/08/2011 02:06 AM, Heinrich Langos wrote: >>> Hi htere, >>> >>> I am using the open-iscsi initiator to access a storage back end for >>> my Xen based virtualization infrastructure. >>> Since The current 3.0.x Linux kernel finally has everything that I >>> need to run the host system (Dom0) without any additional patches I >>> thought I'd give it a try and see if I can replace the 2.6.32 hosts >>> that cause a lot of trouble when mixing Xen + iSCSI + multipath. >>> >>> This is raw "dd" throughput for reading ~30GB from an iSCSI storage >>> via a dedicated 1GB Ethernet link. >>> >>> 2.6.32 : 102 MB/s >>> 2.6.38 : 100 MB/s >>> 2.6.39 : 44 MB/s >>> 3.0.1 : 43 MB/s >>> >> >> I can replicate this now. For some reason I only see it with 1 gig. I >> think my 10 gig setups that I have been testing with are limited by >> something else. >> >> Doing git bisect now to track down the change that caused the problem. >> > > I did not find anything really major in the iscsi code. But I did notice > that if I just disable iptables throughput goes from about 5 MB/s back > up to 85 MB/s. > > If you disable iptables do you see something similar. >
I also noticed that in 2.6.38 throughput would almost immediately start at 80-90 MB/s, but with 2.6.39 it takes a while (maybe 10 seconds sometimes) to ramp up. -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/open-iscsi?hl=en.
