Raid 5 speed issues

May 31, 2008

I have purchased an addon eSATA II card wtih two ports and a box that has

two eSATA 5 port multipliers for a total of 10 disks. I am using Windows

2000 Disk Manager to setup two RAID 5 sets with 5 disks each and each have a

total of almost 2TB available.

I am doing some speed testing with various utilities and it seems that small

liniar and random reads have very poor performance (25 - 50% slower). It is

only when the utilities test larger files above 500 KB where I start seeing

higher performance than just putting a single disk on the controller rather

than the 5 disk stripe.

Is this normal for RAID 5 to have poor small data performance and only

slightly better large file performance?

June 2, 2008

Re: Raid 5 speed issues

I would advise that you look at purchasing a dedicated RAID 5 controller

card. Software is very slow as it adds extra load on the processor, memory

etc of the system

"Jordan" <none@here.com> wrote in message

news:OBcAAsxwIHA.3780@TK2MSFTNGP03.phx.gbl...

>I have purchased an addon eSATA II card wtih two ports and a box that has

>two eSATA 5 port multipliers for a total of 10 disks. I am using Windows

>2000 Disk Manager to setup two RAID 5 sets with 5 disks each and each have

>a total of almost 2TB available.

>

> I am doing some speed testing with various utilities and it seems that

> small liniar and random reads have very poor performance (25 - 50%

> slower). It is only when the utilities test larger files above 500 KB

> where I start seeing higher performance than just putting a single disk on

> the controller rather than the 5 disk stripe.

>

> Is this normal for RAID 5 to have poor small data performance and only

> slightly better large file performance?

>

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