Optimal File System config for 2.5TB RAID5

[Josh Paetzel]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Wojciech Puchar wrote:
>> | | the simple answer is that software RAID on todays computers vastly
>> | outperforms ANY hardware raid solution, maybe except the ones for
>> 10000$ | or more.
>>
>> You're basically correct, but I think you're overestimating the price of
>> a good RAID controller.
> 
> no. please give me example of any RAID hardware below 10000$ that WILL
> be faster than properly configure software RAID solution under FreeBSD
> with same amount of same disks.
> 
> i mean faster under normal unix-like load, which is lots of parallel
> accesses to same or different things, not simple tests.
> 
> 
> there are NONE.

I have a number of systems running postgresql + a python web application
that see fairly heavy concurrent access.

The 3ware 9690SA outperforms gmirror and can be had in 4 port with the
battery for $600 or so.  8 port with a battery is closer to $1000

Hardware RAID gets you boot support from stripes, email alerts for RAID
events in many cases, and with a battery the option to turn write
caching on on the controller.

Unfortunately there are a number of bad and/or poorly supported RAID
controllers out there, especially on FreeBSD.  I'd never suggest to
anyone that my highpoint 2300 or LSI 3041R-E are "high performance", but
on the other hand, at real world tasks like a database that backs up a
webserver doing millions of hits a day, the LSI 320-2E does RAID 10
faster than gvinum, and my 3ware 9690SA's are faster than gmirror at
RAID 1, plus offer the option for a warm spare.

Software RAID has advantages, namely hardware independance.  And it can
be faster than low end hardware RAID.  But you don't have to spend much
to get a hardware solution that will smoke software RAID at real world
applications.


- --
Thanks,

Josh Paetzel

PGP: 8A48 EF36 5E9F 4EDA 5ABC 11B4 26F9 01F1 27AF AECB
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.7 (MingW32)

iD8DBQFI5EbNJvkB8SevrssRAvdLAJ96CLUVK3M2YLKNmAxmIPlxoqp+fgCgnLp6
H1OgEHevOKqDJ/FRg5+fHpU=
=MQFo
-----END PGP SIGNATURE-----