On 28/03/19, Perumal Raj (perucinci@xxxxxxxxx) wrote: > On Sat, Mar 23, 2019 at 3:12 PM Kenneth Marshall <ktm@xxxxxxxx> wrote: > > On Sat, Mar 23, 2019 at 12:09:11PM +0000, Rory Campbell-Lange wrote: > > > On 17/03/19, Rory Campbell-Lange (rory@xxxxxxxxxxxxxxxxxx) wrote: > > > > We aren't sure whether to use software MDRaid or a MegaRAID card. ... > > > > We use MDRaid elsewhere but we've never used it for our databases > > > > before. > > > > > > Apologies for re-heating this email from last week. I could really > > > do with the advice. > > > > > > Has anyone got any general comments on whether software RAID or an > > > LSI card is preferable? ... > > The main reason, in my opinion, to use a HW RAID card is for the NVRAM > > battery backed cache to support writing to traditional spinning disks. > > Since your SSDs have power-loss support, you do not need that and the HW > > RAID controller. For database use, you would almost certainly be using > > RAID 10 and software RAID 10 is extremely performant. I am in the middle > > of setting up a new system with NVMe SSD drives and HW RAID would be a > > terrible bottle-neck and software RAID is really the only realistice > > option. > Just would like to know conclusion here , > > What is best RAID method (Software Or Hardware) for Postgres DB and what > level ? Hi Perumal Ken's comments summarise the general tenor of the advice I've been given. Rory
