java performance in batch of a packaged tool

Investigating a performance issue.

Is there anything (within reason) one can do increase performance in a java
tool (email) which is called from RPGLE.

Not a java programmer.

All the emails are sent to an Exchange server in the same lan.

Batch pool *base has 18-20 gig memory (auto adjust with paging set to
*calc).

Server not heavily loaded but same pool serving cgi web server, no heavy
traffic and no performance issues.

CPU usage during batch process is maybe 4%.

Power 8 and V7R1

Emails taking 30-40 seconds each, for a little text and a 0.5 to 3 meg
attachment.

Average batch process migh send anywhere from 2 to 200.

Two ethernet lines - 1G, Full Duplex, 1496 packet size

This started before the Power 8 upgrade., prev Power 7 also 7.1

Same code & tool, in past (maybe year ago)could send each email in 3-4
seconds - but cannot put a finger on what has changed, other than a catch up
of ptfs - several cumes and all the groups, but with nobody watching, not
positive it started then.

Win Exchange server takes in other bulk email (like scanners) with no
problem.

Can see the jdk is 6.0 (and I know it's going away).

Joblog shows setting environment variables, change directory, and then 30+
seconds later start next one.

Have no logs from when this was faster.



Already looking at other tools so no need to mention.. but a simple tweak
would be nice.



Jim