Re: is the PERC4/Ei worth a look?

[Inaki Sanchez <isanchez unav es>]

Hi:

I have a PERC3/DC on a PE2600 connected to a Dell PowerVault 220s; I know it is not the fastest controller in the world but performs quite well. I think it degrades when configured in cluster mode.
I also have a PE2800 with a PERC4/Ei with excellent performance.

A quick test from it:

[root bibl2005 root]# for i in `seq 1 5`; do hdparm -tT /dev/sda; done

/dev/sda:
Timing buffer-cache reads:   128 MB in  0.24 seconds =533.33 MB/sec
Timing buffered disk reads:  64 MB in  0.34 seconds =188.24 MB/sec

/dev/sda:
Timing buffer-cache reads:   128 MB in  0.21 seconds =609.52 MB/sec
Timing buffered disk reads:  64 MB in  0.32 seconds =200.00 MB/sec

/dev/sda:
Timing buffer-cache reads:   128 MB in  0.22 seconds =581.82 MB/sec
Timing buffered disk reads:  64 MB in  0.28 seconds =228.57 MB/sec

/dev/sda:
Timing buffer-cache reads:   128 MB in  0.19 seconds =673.68 MB/sec
Timing buffered disk reads:  64 MB in  0.35 seconds =182.86 MB/sec

/dev/sda:
Timing buffer-cache reads:   128 MB in  0.25 seconds =512.00 MB/sec
Timing buffered disk reads:  64 MB in  0.36 seconds =177.78 MB/sec

This is my experience, I hope it helps you.

Cheers,

--
Inaki Sanchez
Centro de Proceso de Datos
Universidad de Navarra

mailto:isanchez unav es
http://www.unav.es


Tom Georgoulias wrote:
> Full disclaimer:  I once had a Dell PowerVault 220S connected with a
> PERC3/DC to a Poweredge 2650.  The I/O performance was *so* abysmal and
> caused me such stress that I really don't ever want to work with a PERC
> RAID controller for the rest of my life.
>
> That said, a system using a PERC4/Ei might be on my horizon.  My gut 
> instinct is to lobby against buying it, but I'm trying to be logical and 
> level headed.  ;)  Has anyone who has been burned by the PERC3s in the 
> past worked with the PERC4s?  How do they perform?  I know my DC 
> experience isn't an apples to apples comparison to a Di, but the thought 
> of getting back on the "maybe the next megaraid version or BIOS update 
> will fix the problem?" train is not sitting well with me.
>
> Tom
>
> --
> Taroon-list mailing list
> Taroon-list redhat com
> http://www.redhat.com/mailman/listinfo/taroon-list