Storage Boards Cleanup
To make it easier to find information about HPE Storage products and solutions, we are doing spring cleaning. This includes consolidation of some older boards, and a simpler structure that more accurately reflects how people use HPE Storage.
Disk Arrays
cancel
Showing results for 
Search instead for 
Did you mean: 

How many I/Os per disk

Patrick Terlisten
Honored Contributor

How many I/Os per disk

Hello,

can someone tell me how many I/Os each of this disks can perform?

U320 SCSI, 10k upm
U320 SCSI, 15k upm
SATA 5,4k upm
SATA 7,2k upm

I think that the FATA an FC drives that could pe used in an EVA will handle the same amount of I/Os.

I heared, some years ago, that a 10k upm U320 disk will achieve round about 150 I/Os. A 15k disk achieve 190 I/Os. I don´t have any values for SATA disks.

Thanks for your help.

Regards,
Patrick
Best regards,
Patrick
6 REPLIES
Jefferson Humber
Honored Contributor

Re: How many I/Os per disk

Patrick,

Tricky question, similar to one I asked a little while ago.

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=1014228

Jeff
I like a clean bowl & Never go with the zero
Patrick Terlisten
Honored Contributor

Re: How many I/Os per disk

Hello Jefferson,

according to your thread I think that my 150 I/Os may be a realistic value.

10000 upm / 60 seconds = ca. 167 I/Os
15000 upm / 60 seconds = ca. 250 I/Os

If a disk do one I/O per rotation, this formula will give me values for a "perfect world enviroment". But IMHO can do a disk more than one I/O per second, depending on the number of write / read heads and disks in the harddrive, right?

Regards,
Patrick
Best regards,
Patrick
John Kufrovich
Honored Contributor

Re: How many I/Os per disk

>But IMHO can do a disk more than one I/O >per second, depending on the number of >write / read heads and disks in the >harddrive, right?

Patrick,
Look at the your results and reread your statement above. Yes, a drive can do more than 1 I/O ps.

The mechanics of any hard drive limits the number of I/Ops. Sequential access will give you high IOps than random. Realistically 15k, sequential performance will be around 150IOps. This number is taking into account for seeks.

jk
Cass Witkowski
Trusted Contributor

Re: How many I/Os per disk

This URL may have the answers you are looking for.

http://www.hp.com/products/harddiskdrives


Also remember that SATA drives have a much lower duty cycle rating. This means that if your are expecting to use the drives with a duty cycle of 20%- 30% then you should look at the SCSI drives.
Lethuillier
Frequent Advisor

Re: How many I/Os per disk

Take a look at this comparison sheet :

http://www.westerndigital.com/en/library/sata/2579-001097.pdf
Il faut avoir la foi et non les foies - Il faut avoir la forme et non les formes - Il faut faire la paix et non des pets
Patrick Terlisten
Honored Contributor

Re: How many I/Os per disk

Thanks for your replies. The link to Western Digital is nice, but a little bit "WD minded". ;)

Regards,
Patrick
Best regards,
Patrick