Re: New server: SSD/RAID recommendations?

On Wed, Jul 1, 2015 at 4:56 PM, Andreas Joseph Krogh <andreas(at)visena(dot)com>
wrote:

> På torsdag 02. juli 2015 kl. 01:06:57, skrev Craig James <
> cjames(at)emolecules(dot)com>:
>
> We're buying a new server in the near future to replace an aging system.
> I'd appreciate advice on the best SSD devices and RAID controller cards
> available today.
>
> The database is about 750 GB. This is a "warehouse" server. We load
> supplier catalogs throughout a typical work week, then on the weekend
> (after Q/A), integrate the new supplier catalogs into our customer-visible
> "store", which is then copied to a production server where customers see
> it. So the load is mostly data loading, and essentially no OLTP. Typically
> there are fewer than a dozen connections to Postgres.
>
> Linux 2.6.32
> Postgres 9.3
> Hardware:
> 2 x INTEL WESTMERE 4C XEON 2.40GHZ
> 12GB DDR3 ECC 1333MHz
> 3WARE 9650SE-12ML with BBU
> 12 x 1TB Hitachi 7200RPM SATA disks
> RAID 1 (2 disks)
> Linux partition
> Swap partition
> pg_xlog partition
> RAID 10 (8 disks)
> Postgres database partition
>
> We get 5000-7000 TPS from pgbench on this system.
>
> The new system will have at least as many CPUs, and probably a lot more
> memory (196 GB). The database hasn't reached 1TB yet, but we'd like room to
> grow, so we'd like a 2TB file system for Postgres. We'll start with the
> latest versions of Linux and Postgres.
>
> Intel's products have always received good reports in this forum. Is that
> still the best recommendation? Or are there good alternatives that are
> price competitive?
>
> What about a RAID controller? Are RAID controllers even available for
> PCI-Express SSD drives, or do we have to stick with SATA if we need a
> battery-backed RAID controller? Or is software RAID sufficient for SSD
> drives?
>
> Are spinning disks still a good choice for the pg_xlog partition and OS?
> Is there any reason to get spinning disks at all, or is it better/simpler
> to just put everything on SSD drives?
>
> Thanks in advance for your advice!
>
>
>
> Depends on you SSD-drives, but today's enterprise-grade SSD disks can
> handle pg_xlog just fine. So I'd go full SSD, unless you have many BLOBs in
> pg_largeobject, then move that to a separate tablespace with
> "archive-grade"-disks (spinning disks).
>

No blobs in our database, so that sounds like good advice. It simplifies
the hardware a lot if we can go with just SSDs.

Craig

>
> --
> *Andreas Joseph Krogh*
> CTO / Partner - Visena AS
> Mobile: +47 909 56 963
> andreas(at)visena(dot)com
> www.visena.com
> <https://www.visena.com>
>
>

--
---------------------------------
Craig A. James
Chief Technology Officer
eMolecules, Inc.
---------------------------------