`<div dir="ltr">Hi Matej,<br><br>Do you have sar running on your system? I'd recommend maybe running it at a short interval so that you can get historical disk statistics. You can use this info to rule out if its the disks or not. You can also use iotop -P to get a real time view of %IO to see if it's the disks. You can also use zpool iostat -v 1.<br><br>Also, do you have baseline benchmark of performance and know if you're meeting/exceeding it? The baseline should be for random and sequential IO; you can use bonnie++ to get this information.<br><br>Are you able to share your ZFS configuration and iSCSI configuration?<br><br>For iSCSI, can you take a look at this: <a href="http://docs.oracle.com/cd/E23824_01/html/821-1459/fpjwy.html#fsume">http://docs.oracle.com/cd/E23824_01/html/821-1459/fpjwy.html#fsume</a><br><br>Do you have detailed logs for the clients experiencing the issues? If not are you able to enable verbose logging (such as debug level logs)?<br><br>Regards,<br>Josten Landtroop<br><br></div>
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