Note that with linux (and a few other OSes) you can use RAID-1E http://en.wikipedia.org/wiki/Non-standard_RAID_levels#RAID_1E with an odd number of drives. On Fri, May 3, 2013 at 12:16 AM, Arjen van der Meijden <acmmailing@xxxxxxxxxxxx> wrote: > 3x200GB suggests you want to use RAID5? > > Perhaps you should just pick 2x200GB and set them to RAID1. With roughly > 200GB of storage, that should still easily house your "potentially > 10GB"-database with ample of room to allow the SSD's to balance the writes. > But you save the investment and its probably a bit faster with writes > (although your raid-card may reduce or remove the differences with your > workload). > > You can then either keep the money or invest in faster cpu's. With few > concurrent connections the E5-2643 (also a quad core, but with 3.3GHz cores > rather than 2.4GHz) may be interesting. > Its obviously a bit of speculation to see whether that would help, but it > should speed up sorts and other in-memory/cpu-operations (even if you're not > - and never will be - cpu-bound right now). > > Best regards, > > Arjen > > > On 3-5-2013 1:11 Mike McCann wrote: >> >> Hello, >> >> We are in the fortunate situation of having more money than time to help >> solve our PostgreSQL 9.1 performance problem. >> >> Our server hosts databases that are about 1 GB in size with the largest >> tables having order 10 million 20-byte indexed records. The data are >> loaded once and then read from a web app and other client programs. >> Some of the queries execute ORDER BY on the results. There are >> typically less than a dozen read-only concurrent connections to any one >> database. >> >> SELECTs for data are taking 10s of seconds. We'd like to reduce this to >> web app acceptable response times (less than 1 second). If this is >> successful then the size of the database will grow by a factor of ten - >> we will still want sub-second response times. We are in the process of >> going through the excellent suggestions in the "PostgreSQL 9.0 High >> Performance" book to identify the bottleneck (we have reasonable >> suspicions that we are I/O bound), but would also like to place an order >> soon for the dedicated server which will host the production databases. >> Here are the specs of a server that we are considering with a budget of >> $13k US: >> >> HP ProLiant DL360p Gen 8 >> Dual Intel Xeon 2.4GHz 4-core E5-2609 CPUs >> 64GB RAM >> 2x146GB 15K SAS hard drives >> 3x200GB SATA SLC SSDs >> + the usual accessories (optical drive, rail kit, dual power supplies) >> >> Opinions? >> >> Thanks in advance for any suggestions you have. >> >> -Mike >> >> -- >> Mike McCann >> Software Engineer >> Monterey Bay Aquarium Research Institute >> 7700 Sandholdt Road >> Moss Landing, CA 95039-9644 >> Voice: 831.775.1769 Fax: 831.775.1736 http://www.mbari.org >> > > > -- > Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-performance -- To understand recursion, one must first understand recursion. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
