Hi,
We're currently running IMail 7.15-HF3 and are considering upgrading to IMail 8. Before we make the decision, there are a number of outstanding support issues that have not been resolved, which make me reticent to go down this route. Hopefully you can help sort these out once and for all?
The software "appears" to be very inefficient, but I am not sure if it is the way that we have it configured. We're handling between 25k and 30k messages a day (~18k local, ~10k outbound) with Win2k on a dual P3-933Mhz, 512MB memory, on 2 Ultra-160 SCA SCSI drives configured with RAID1. IMail is configured to use the registry for lookups, containing approx 2k domains. The spool and mailboxes are currently stored on the same partition, but I'm not seeing the disc read/write queues reach levels to warrant changing this.
The problems we've had are always to do with CPU time used by either the smtpd32.exe or smtp32.exe processes. In the last month, the server CPU usage has been averaging 93%, starving the web interface of CPU time - it looks very bad when it takes up to 5 seconds for the web login page to display. My experiments with PerfMon show that disc I/O is not a bottleneck at all, it is always lack of CPU resources.
It can mainly be attributed to smtp32.exe delivering messages, as these processes are at times using 47% CPU each. It seems to spend an awful lot of time (subjective) making registry lookups (watching with Process Explorer from sysinternals.com)... I'm in the process of trying to get a Win32 API profiler working, to see where smtp32.exe is spending most of that CPU time; but having some problems with getting APIMon working atm.
Since it's a production environment, it's difficult to do intrusive tests. It's simple enough to duplicate the software configuration, but then it won't be running under the same load.
Main questions:
* Should this hardware be able to handle that number of messages per day? Is anyone else out there handling similar amounts of mail on equivalent hardware?
I have other non-IMail boxes handling over 250k messages a day on much lower-spec hardware. * Is the registry a known bottleneck for IMail? Should I consider writing a DLL to move over to SQL? * Could I perhaps modify IMail such that the web interface runs on a different server from where the mailboxes are stored?
TIA,
-- Jon Miles <[EMAIL PROTECTED]> Cybah on IRC(net)
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