________________________________________ From: pgsql-performance-owner@xxxxxxxxxxxxxx <pgsql-performance-owner@xxxxxxxxxxxxxx> on behalf of Evgeniy Shishkin <itparanoia@xxxxxxxxx> Sent: Thursday, December 11, 2014 7:11 AM To: Andrea Suisani Cc: mfatticcioni@xxxxxxxxxxx; pgsql-performance@xxxxxxxxxxxxxx Subject: Re: Tuning the configuration > On 11 Dec 2014, at 15:02, Andrea Suisani <sickpig@xxxxxxxxxxxx> wrote: > > On 12/10/2014 11:44 AM, Maila Fatticcioni wrote: >> 2- I would like to use the two SDD to store the wal file. Do you think >> it is useful or how should I use them? > > I definitely would give it a try. > > I don't understand the logic behind using drives, > which are best for random io, for sequent io workloads. > Better use 10k sas with BBU raid for wal, money wise. Very much agree with this. Because SSD is fast doesn't make it suited for certain things, and a streaming sequential 100% write workload is one of them. I've worked with everything from local disk to high-end SAN and even at the high end we've always put any DB logs on spinning disk. RAID1 is generally sufficient. SSD is king for read heavy random I/O workload. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
