Side note about Linux I/O experience
1. One of the work PCs runs 4-disk Linux MD RAID-10.
2. I ran some simple benches and everything reasonable for single user.
3. This host exports NFS to VMWARE for VM Storage.
On this particular occasion,
4. only one test Windows VM doing dir c:\ /s
5. The Linux desktop response became sluggish.
6. I was surprised because it should have no problem with such light load.
7. iostat - IOPS wasn't extreme.
Finally I did the necessary adjustment for all the drives, example for one of the drives
echo deadline > /sys/block/sda/queue/scheduler
8. Now everything back to reasonable.
My Tentative experience.
I think the default I/O Scheduler (CFQ) maybe I need more understanding and tuning for non-desktop cases. For me at least, deadline I/O Scheduler seems to be reasonable in most cases. I am not a top performance seeker.
1. One of the work PCs runs 4-disk Linux MD RAID-10.
2. I ran some simple benches and everything reasonable for single user.
3. This host exports NFS to VMWARE for VM Storage.
On this particular occasion,
4. only one test Windows VM doing dir c:\ /s
5. The Linux desktop response became sluggish.
6. I was surprised because it should have no problem with such light load.
7. iostat - IOPS wasn't extreme.
Finally I did the necessary adjustment for all the drives, example for one of the drives
echo deadline > /sys/block/sda/queue/scheduler
8. Now everything back to reasonable.
My Tentative experience.
I think the default I/O Scheduler (CFQ) maybe I need more understanding and tuning for non-desktop cases. For me at least, deadline I/O Scheduler seems to be reasonable in most cases. I am not a top performance seeker.
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