I don't know why iSCSI so slowly..
Hi, there.
I've some question, about rhev storage domain server is so slow.
I create vm on my hypervisor1 server.
os install is remaning 7hours... is that a something problem right..
i don't know is there..
Responses
Hi,
Please provide some details:
- Storage configuration and properties (type, spindle count and types, path count, network speed and type etc)
- VM type, guest OS, configuration
- Installation source details (ISO domain/PXE server/how configured/how it is accessed)
OK, so you have a single 1kmbps path to the iSCSI server, which is based on slow, non-enterprise disks.
Where do you export the installation image from? I mean where is the NFS server? How is it configured (what's in /etc/exports)
Also, do you use virtio or IDE for the VM disk image?
And one last question - have you measured the actual baremetal speeds of reading from the NFS, and writing to the iSCSI LUN?
I guess storageSV is your iSCSI server? What I meant is to measure the iscsi access speeds from theRHEV hypervisor, not locally
sure, go into the root shell of the hypervisor, make sure your iscsi target is connected, create a spare LV on it, and dd if=/dev/zero of=/dev/mapper/test-LV bs=512 count=20000
Should be good enough.
Don't forget to get rid of the test LV after you're done
yes, it shows dm-10 is the target. It's writing at about 60MBps and reading at about 30MBps. The write speed seems to be acceptable, for a single 1Gbps path.
So I think you might have a bottleneck on the NFS side of things. Can you try to remount the partition that holds your NFS share with the noatime and nodiratime options?
No, this doesn't look normal at all.
But you have to test with bs=512 first.
How is the iSCSI server configured?