Active IQ Unified Manager Discussions

Do IOPS on Aggregate Performance Report include IO from cache Hits?

husselbees
15,386 Views

Hi - I'm looking to find (for each aggregate in a FAS3070 Filer) how many IOPS are being delivered at peak.

I'm working on the theory that each data disk should be capable of delivering approx 180 IOPS (they're 15k FC disks), hence I can create a "theoretical" performance limit for each aggregate, (180 x number of data disks), beyond which latency is likely to suffer.

The reason I want to know is that we are considering moving to 300GB disks, but there is little point in getting extra capacity if I can't practically make use of it (I get double the capacity but I get no more performance).

My storage admnistrator has produced an Operations Manager aggregate report (OPS Manager – ‘dfm report view aggregates-performance-summary’) showing at peak a level of IOPS that would equate to approx 600 IOPS per data disk.

600 IOPS per disk doesn't sound realistic (nobody is complaining of poor latency/performance)

Could it be that the aggregate performance report is including IOPS from Cache Hits??? (In which case this is the wrong report for me - I am purely interested in Disk IOPS).

Can anyone help?

Stu

P.S. Summary below:

Filer Name

Aggregate

# Data
Disks

Theoretical
IOPS
maximum

Monitored
IOPS

% utilised

Filer1

aggr1

70

12601

10748

85%

Filer2

aggr1

68

12241

8841

72%

Filer3

aggrebg

47

8461

10239

121%

Filer4

aggr1

37

6661

21168

318%

27 REPLIES 27
Public