Re: RAID + PostgreSQL?

-----Ursprüngliche Nachricht-----
Von: Alex Turner [mailto:armtuk@gmail.com]
Gesendet: Dienstag, 4. Juli 2006 04:10
An: Franz.Rasper@izb.de
Cc: smarlowe@g2switchworks.com; pgsql-general@postgresql.org
Betreff: Re: [GENERAL] RAID + PostgreSQL?

Of course if you really want good performance, 6 drives is a little light, and U320 is definatley not the way to go as you are limited to 320MB/sec per channel (an the DL380 comes with all drives on one channel) (not that you could saturate that with only 6 drives in RAID 10 anyway).  Given that this chap has 13 disks already, a DL380 is probably not what he is looking for.  Consider SAS for better performance.

Alex

On 6/28/06, Franz.Rasper@izb.de <Franz.Rasper@izb.de> wrote:

How much I/O Performance do you need ?

READ Performance ? Write Performance ?

I need an fast and reliable RAID Controller (harddisks have to be hot plug,
automatic rebuild etc.)
and I have to say that the HP DL 380 G 4 with Battery Backup Write Cache ,
FAST U320 HDs,
some gigs ram (chipkill is a nice feature), redundant fans and power
supplies is a good database server.
Unfortunately I had no chance to test the HP DL 385.

Greetings,

-Franz

-----Ursprüngliche Nachricht-----
Von: Scott Marlowe [mailto: smarlowe@g2switchworks.com]
Gesendet: Dienstag, 27. Juni 2006 17:45
An: Franz.Rasper@izb.de
Cc: teolupus@gmail.com; pgsql general
Betreff: Re: [GENERAL] RAID + PostgreSQL?


On Tue, 2006-06-27 at 08:05, Franz.Rasper@izb.de wrote:
> I have here HP DL 380 G3 und HP DL 380 G4. (here Smart Array 5i and Smart
> Array 6i)
> Maybe there are problems with old linux kernel (but as far as i know >
> 2.4.27)
> I dont know about such performance problems, maybe the conrollers are
faster
> under windows.
>
> The battery backup write cache are very import for inserts.
>
> You should use for performance test with dd under linux larger blocksizes,
> but you should compare postgresql under linux and windows (selects,
update,
> inserts, etc.)

Note that having the latest driver usually helps a lot too.

The LSI megaraid was solid but a mediocre performer with the older 1.18
driver, but the 2.x series driver was much faster when I tested it.

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