On Tue, Sep 07, 2010 at 09:07:54PM +0200, lst_ho...@kwsoft.de wrote:
>> Single-core CPU limit. The system had 4 CPUs and the load peaked at ~25%.
>> The queue manager is single-threaded, and must do a fair amount of message
>> envelope processing. So the current design tops out at ~2-3k msgs/sec,
>> which is substantially faster than other constraints on real systems, so
>> the queue manager is not your bottleneck in real systems.
>
> Ok, so if one wants to really peak out it is more useful to have less
> cores, but faster ones given that I/O is able to keep up.
Purely hypothetical discussion, no real MTA handles > 1k messages every
second. Yes, a single faster core improves the impractically high ceiling
on queue manager throughput when the disk subsystem is so fast that the
queue manager is CPU rather than I/O constrained. Today's practical queue
managers with queues on spinning disks will get bogged down in I/O first.
--
Viktor.
