MSA1000 questions

[James Prendergast]

I have a few questions about an MSA1000:

We have a 900GB RAID 5 array. It's broken down into 5 logical drives. Whenever we expand any of the drives into the unused space it takes forever. I added 50GB to LD 3 and it has taken 2 weeks so far to rebuild and still isn't finished. It's set to the low expand priority. How much of an impact will it cause on I/O if I set it to high? This is on a client facing array so we have to be very careful not to affect performance. What kind of increase in speed will I see at medium? TIA

[Phillip Thayer · Accepted solution]

The impact on performance id dependent on how much cache you have on your controller. The more cache you have the less impact to the performance if you set the expand priority to medium or high. You WILL see a performance impact but with more cache you will see less. What you might consider is setting the expand priority to high during non-peak load times and setting it back to low during peak load times. That would allow it to complete sooner.

Phil

[James Prendergast]

Thank you and that also answers my question of whether or not you can change that expand priority midstream.