On 23.3.2012, at 19.43, <l...@airstreamcomm.net> <l...@airstreamcomm.net> wrote:
>> Have you tried stress testing it with imaptest? Run in parallel for both >> servers: > I did stress test it, but we have developed a "mail bot net" tool for the > purpose. I should mention this was tested using dovecot 1.2, as this is > our current production version (hopefully will be upgrading soon). Its > comprised of a control server that starts a bot network of client machines > that creates pop/imap connections (smtp as well) on our test cluster of > dovecot (and postfix) servers. In my test I distributed the load across a > two node dovecot (/postfix) cluster back ended by glusterfs, which has SAN > storage attached to it. I actually didn't change my configuration from > when I had a test NFS server connected to the test servers (mmap disabled, > fcntl locking, etc), because glusterfs was an afterthought when we were > stress testing our new netapp system using NFS. We have everything in > VMware, including the glusterfs servers. Using five bot servers and > connecting 7 times a second from each server (35 connections per second) > for both pop and imap (70 total connections per second) split between two > dovecot servers I was not seeing any big issues. The load average was low, > and there were no errors to speak of in dovecot (or postfix). I was > mounting the storage with the glusterfs native client, not using NFS (which > I have not tested). I would like to do a more thorough test of glusterfs > using Dovecot 2.0 on some dedicated hardware and see how much further I can > push the system. What did the bots do? Add messages and delete messages as fast as they could? I guess that's mostly enough to see if things work. imaptest anyway hammers the server as fast as it can with all kinds of commands.