question about different disk size in xp1024

[Mark Harshman_1]

hello, I have an xp1024 with approx 8TB of space. all drives are currently 73 GIG drives. we are considering adding some 143 GIG drives. I am concerned about whether i should do this, or if there would much of a performance hit with these added disks of a different size. any help would be appreciated. thanks

[charles butkus]

I haven't looked into it lately (ask your ASE about it..) but generally, the smaller the spindles, the faster they are... at least on the XP512 Frame...

[Ted Buis · Accepted solution]

Adding more drives of any size will not affect the performance of existing LUNs other than the impact on cache and additional I/Os that might be associated with the new LUNs. You could use mirroring with the higher capacity drives versus RAID 5 with smaller ones, but the 146GB disks are likely to be 10,000 rpm and the 73GB might be 10,000 or 15,000 rpm depending on the model. So the question is how many I/Os per second (IOPS) do you really need from these new LUNs? Are they going to be mirrored or RADID 5? What is the I/O block size? Will access be random or sequential? HP has tools to estimate performance on the XP1024, so one of the Storage Solution Architects should be able to help tell you how many disks of any size you would need for the array to be able to deliver the number of IOPS you say you need.

[Sunil Sharma_1]

Hi,

I have an EMC box wih 26,72 and 140 GIG HDD and my personal experience is 140 GIG hard disk has very slow responce with comarisn to other two becoz of it's low spindle rate (7.4K or 10K).

It's always batter to use lowe capacity disk for batter performence.

Sunil

[Sanjay Kumar Suri]

Dear

We have recently added some TB of space to our XP1024. To the best of my knowledge, this has not not affected the performance.

We are keeping datafile on RAID5 on the LUNs created out of 146 GB disks. Database redo log files are kept on higher RPM (smaller disks) for better performance.

Summary is: Disk capacity is increasing. Storage requirment is increasing. Space in XP1024 is limited. Else you need to add more DKC.

One Catch: You may have to incrase the shared memory in order to use higher capacity disks (146 GB). Check with Support team on this.

sks