Fabio Sangiovanni wrote: >I need to setup an environment made up of multiple MTAs to accept >incoming mail, in load balance configuration. ... >2) x MTAs + 1 external policyd daemon (used by all MTAs) + 1 external db
I've gone with that option for my little cluster >How will a single policyd daemon deal with the load of multiple >(let's say 5) high-traffic (>20.000 mail/day/mta) MTAs? Of course >I'll set the number of policyd concurrent threads accurately. I had some performance issues to start with, but then I did a software update and a slightly newer MySQL server seemed to cure it. From memory they related to the connection being lost between policy server and DB engine. The next bottleneck I hit was with Postfix itself. Again from memory, but I think it seems to be limited to about 2 messages/second/thread* when calling the policy server. I did some stress tests and found that the backend policy server could keep up with multiple hosts, each running two threads, without having a particularly powerful host (can't really give specs, dedicated virtual machine for the backend policy server/DB running under Xen along with multiple other VMs). My target was to handle about 20k messages/day total, but heavily biased towards office hours and I wasn't worried about the backend being a problem. * Actually, 2 recipients/second/thread. I was throwing large numbers of messages, each with large numbers of recipients, into the queue on multiple hosts. It's easy to throw lots of requests at the policy server with something like netcat a short shell script to loop round lots of times. I just captured a query from the detailed logs and used that multiple times. -- Simon Hobson Visit http://www.magpiesnestpublishing.co.uk/ for books by acclaimed author Gladys Hobson. Novels - poetry - short stories - ideal as Christmas stocking fillers. Some available as e-books. _______________________________________________ Users mailing list [email protected] http://lists.policyd.org/mailman/listinfo/users
