zfs iops on nfs iscsi disk
On zfs storage 7000 series BUI, you may found the following statistic:
This may seem quite weird as you can see that, NFSv3(3052) + iSCSI(1021) is larger than Disk(1583). As iops for protocal NFSv3/iSCSI finally goes to Disk, so why iops for the two protocals is larger than Disk iops?
Here's the reason:
Disk operations for NFSv3 and iSCSI are logical operations. These logical operations are then combined/optimized by sun zfs storage and then finally go to physical Disk operations.
1.When doing continuous access to disks(like VOD), disk throughputs will become the bottleneck of performance rather than IOPS. In constract, IOPS limits disk performance when random access is going on disks.
2.For NAS performance analytic, here are two good articles(in Chinese) http://goo.gl/Q2M7JE http://www.storageonline.com.cn/storage/nas/the-nas-performance-analysis-overview/
3.You may also wonder why Disk iops can be as high as 1583. As this number is the sum of all disk controllers of the zfs storage system. Here's some ballpark numbers for HDD iops: