We have fiber channel in production and iscsi in development. Both
work well but iscsi is definitely slower. In our case the iscsi disks
are slower too so that likely affects our speed on iscsi.
Sent from my iPod
On Sep 21, 2009, at 4:24 PM, "John R Pierce" <pie...@hogranch.com>
wrote:
Scot Kreienkamp wrote:
> On the contrary, we've been running PG in production for years now
under VMWare. Same with MSSQL. We've never had any problems. Less
so than an actual physical machine actually since we can move the
server to different physical hardware on demand. Also makes
disaster recovery MUCH easier.
>
> However, VMWare does have its places. A high usage database is
not one of them, IMHO. A moderately or less used one, depending on
requirements and the hardware backing it, is often a good fit. And
I agree with Scott about the snapshots. They do tend to cause
temporary communication issues with a running virtual machine
occasionally, regardless of OS or DB type. (The benefits outweigh
the risks 99% of the time though, with backups being that 1%.) In
my experience the level of interference from snapshotting a virtual
machine also depends on the type and speed of your physical disks
backing the VMWare host and the size of the virtual machine and any
existing snapshot. I've been told that in VSPhere (VMWare 4.0) this
will be significantly improved.
>
does your VMWARE server use NFS to communicate with the disks? It
was
my understanding most folks used SAN logical units for the virtual
disks
with VMware ESX, and not NFS/NAS