Thanks kindly for your reply > There is no fundamental reason why pickup->cleanup is slower than > smtpd->cleanup (other than different receive_override_options > settings in master.cf). > > However, it is possible that you're sending mail INTO Postfix at > a slower rate than expected. > > Specifically, you are sending mail into Postfix via the loopback > interface address. It would be instructive to see if the delay > goes away when you use the NON-localhost interface address instead.
Have just tested using an address on an external interface as requested and there is no change. Mail received over the external interface from remote servers is also subject to slow processing in cleanup but there may be concurrent factors at work there. Clearly postfix is capable of handling messages with large attachments quickly on this machine as evidenced by submissions via pickup, but I'm still stumped as to what may be preventing this via smtp. > The reason I mention this is that OpenBSD uses a large MTU on the > loopback interface (approx. 32 kbytes). If the mail sending app > uses a smaller write buffer, then it will experience NAGLE delays > of a tenth of a second or so, and that adds up with large messages. Interesting, I was not aware of this. -- Dave Green
