The most critical bit of advice I've found is setting this preference: https://amplitude.engineering/how-a-single-postgresql-config-change-improved-slow-query-performance-by-50x-85593b8991b0
I'm using 4 512GB Samsung 850 EVOs in a hardware RAID 10 on a 1U server with about 144 GB RAM and 8 Xeon cores. I usually burn up CPU more than I burn up disks or RAM as compared to using magnetic where I had horrible IO wait percentages, so it seems to be performing quite well so far. Matthew Hall > On Apr 9, 2018, at 7:36 PM, Craig James <cja...@emolecules.com> wrote: > > One of our four "big iron" (spinning disks) servers went belly up today. > (Thanks, Postgres and pgbackrest! Easy recovery.) We're planning to move to a > cloud service at the end of the year, so bad timing on this. We didn't want > to buy any more hardware, but now it looks like we have to. > > I followed the discussions about SSD drives when they were first becoming > mainstream; at that time, the Intel devices were king. Can anyone recommend > what's a good SSD configuration these days? I don't think we want to buy a > new server with spinning disks. > > We're replacing: > 8 core (Intel) > 48GB memory > 12-drive 7200 RPM 500GB > RAID1 (2 disks, OS and WAL log) > RAID10 (8 disks, postgres data dir) > 2 spares > Ubuntu 16.04 > Postgres 9.6 > > The current system peaks at about 7000 TPS from pgbench. > > Our system is a mix of non-transactional searching (customers) and > transactional data loading (us). > > Thanks! > Craig > > -- > --------------------------------- > Craig A. James > Chief Technology Officer > eMolecules, Inc. > ---------------------------------
