HPE Storage Users Group

Hi All,

Can anybody please tell if there is any Optimum Avg busy time for reach type of drive (FC, SSD, NL).

Regards,
KK

Avg Busy % - anything below 100% for any type of drive
You should be paying close attention to Service Time. For FC and NL drives anything above 20ms - not good.
For SSD - they are usually around 0.5ms.

Thanks for the quick reply..


Let me chekc and get back to you

Hi..

I have one more question.

Please tell me the threshold IOPS for SSD, FC and NL.

Regards,
KK

Highly recommend to the following read so you can understand concepts of IOPS per PD
http://www.techrepublic.com/blog/the-en ... age-array/

Also read 3PAR concept guide as it is not your traditional array. With features such as AO, Adaptive Flash Cache, looking at the IOPS for PDs doesn't count for much.

SSD it will depend on which ones, but several thousand minimum, FC will be under 300 to keep service times in the acceptable range, NL would be 50 (and many folks will put in zero for sizing purposes as they don't want any IOPS coming out of the NL tier, it should mostly be stale data under ideal circumstances).

Thanks for the Reply..

So for example if we create a LUN in FC the IOPS should be below 300 consistently (if we take Report in System reporter) and service time should be below 10 ms.

And for LUN from NL should be almost 0 and service time should be below 20 ms.

And for LUN from SSD can be several thousands.

Is this correct??

It depends on the number of drives in the CPG, the RAID type, what workload you're driving, etc.

I was always told to expect ~3000 IOPS per SSD, ~180 IOPS per 15k FC, ~150 IOPS per 10k FC, and ~70 IOPS per NL. As you expand your disk count, your total performance should go up in a linear fashion.

HP should be able to generate a predictive performance report (I attached an example) based upon your current configuration, but you could probably get a good idea with a bit of math.

AdamKnox,

Thank you so much for the neat explanation.

I will analyse again and make some calculations and get back to you.

Thanks