Hmm. I've now upgraded to Dovecot 0.99.10.4, and it doesn't appear to have helped much, if at all.
Between 18:28 yesterday and 10:58 today, the number of pop3-login processes has risen from 12 to 186.
Just for reference, I've gdb-ed the earliest of those processes again:
(gdb) p clients->nodes_count $1 = 0 (gdb) p main_refcount $2 = 2 (gdb) p auth_reconnect $3 = 0 (gdb) p auth_waiting_handshake_count $4 = 0 (gdb) p closing_down $5 = 1 (gdb) p process_per_connection $6 = 1 (gdb) p ssl_proxies->nodes_count Error accessing memory address 0x10: Invalid argument. (gdb) p ssl_proxies $7 = (struct hash_table *) 0x0 (gdb) p io_master $8 = (struct io *) 0x151e0 (gdb) p *io_master $9 = {next = 0x0, fd = 3, condition = 1, destroyed = 0, callback = 0x4c50 <master_input>, context = 0x0}
This looks exactly as before, except that the master_input function has moved by 32 bytes.
There's clearly still something going wrong, somewhere. )-8
Regards,
--Clive.