On 25.11.2013 22:01, Lee Nguyen wrote:
Hi, Having attended a few PGCons, I've always heard the remark from a few presenters and attendees that Postgres shouldn't be run inside a VM. That bare metal is the only way to go. Here at work we were entertaining the idea of running our Postgres database on our VM farm alongside our application vm's. We are planning to run a few Postgres synchronous replication nodes. Why shouldn't we run Postgres in a VM? What are the downsides? Does anyone have any metrics or benchmarks with the latest Postgres?
I've also heard people say that they've seen PostgreSQL to perform worse in a VM. In the performance testing that we've done in VMware, though, we haven't seen any big impact. So I guess the answer is that it depends on the specific configuration of CPU, memory, disks and the software. Synchronous replication is likely going to be the biggest bottleneck by far, unless it's mostly read-only. I don't know if virtualization will have a measurable impact on network latency, which is what matters for synchronous replication.
So, I'd suggest that you try it yourself, and see how it performs. And please report back to the list, I'd also love to see some numbers!
- Heikki -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
