Hi All, I have an issue I can't seem to really solve at present and that is that disk speeds inside the KVMs are really slow.
4 disk Raid10 array on a 3Ware/LSI 9750 controller, Sata III HDDs.
Disk Read on Host Node: 1073741824 bytes (1.1 GB) copied, 1.08169 s, 993 MB/s
Disk Read inside 8gb KVM: 1073741824 bytes (1.1 GB) copied, 3.79095 s, 283 MB/s
Now I also have an SSD on the node, so I even tried fooling around with Flashcache and the same results, the actual disk reads won't increase. They drop as low as 180MB/s, it's like it literally refuses to go beyond 300MB/s. Cache for the KVMs is set to "No Cache."
Any pointers as to what is limiting the disk reads inside KVM would be appreciated. HDD mode is Virtio/Raw.
4 disk Raid10 array on a 3Ware/LSI 9750 controller, Sata III HDDs.
Disk Read on Host Node: 1073741824 bytes (1.1 GB) copied, 1.08169 s, 993 MB/s
Disk Read inside 8gb KVM: 1073741824 bytes (1.1 GB) copied, 3.79095 s, 283 MB/s
Now I also have an SSD on the node, so I even tried fooling around with Flashcache and the same results, the actual disk reads won't increase. They drop as low as 180MB/s, it's like it literally refuses to go beyond 300MB/s. Cache for the KVMs is set to "No Cache."
Any pointers as to what is limiting the disk reads inside KVM would be appreciated. HDD mode is Virtio/Raw.
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