David Gauthier <davegauthierpg@xxxxxxxxx> writes: > Hi: > > I'm going to be requesting a PG DB instance (v9.6.7) from an IT dept in a > large corp setting. I was wondering if anyone could comment on the > pros/cons of getting this put on a virtual machine vs hard metal ? Locally > mounted disk vs nfs ? > This is a hard question to answer as there are too many variables. However, I would say that my experience has been that most large organisations are pretty much using VMs for everything, so asking for something on a 'bare metal' basis is likely to result in your request needing special attention and justification. On the other hand, if you make a standard request, it will likely be fulfilled more rapidly. Sys admins are likely to be resistant to a bare metal setup if their infrastructure is based around VMs due tot he additional work and maintenance overheads. All our databases are running on VMs. Some of them are storing fairly large amounts of data (i.e. one application stores large amounts of weather data - adding 650 million records a day with a consolidation after every 100 days. Currently, the DB is using about 6Tb, so not huge, but not insignificant). Disk storage is via SAN. Getting the right performance will require tweaking of memory, cpus etc. The good news is that adding additional memory and CPUs is relatively trivial. For our situation, VMs have been fine and there has been some advantages with SAN storage infrastructure, such as fast snapshots for backups etc. In general, I usually find it best to work with the system admins and follow their recommendations. Provide them with details of your performance requirements and where you feel resource demands may peak and let them propose what they feel would be best suited given whatever infrastructure they have. Tim -- Tim Cross
