These are tips for managing a busy Simple Mail Transfer Protocol (SMTP) server that uses multiprocessing.
Your SMTP server might be busy because it uses all its capacity for adding and ending prestart jobs for each e-mail request.
If you find that the number of prestart jobs is affecting system performance, you can set the threshold lower. If you want more jobs, you can set the number of prestart jobs higher.
With prestart jobs, every e-mail request runs as its own job. This method allows each job to focus solely on its client or server program's needs and requests. Each job can make longer time-out calls to enable the posting of host names for the purpose of not receiving unsolicited bulk e-mail.
To manage a busy SMTP server, you can change the following values:
To manage a busy system, you need to change values on the SMTP server and the SMTP client.
The SMTP server works with the daemon and prestart jobs: QTSMTPSRVD and QTMSMTPSRVP. The SMTP client works with the daemon and prestart jobs: QTSMTPCLTD and QTSMTPCLTP.
To change the values on the SMTP server, follow these steps:
| Prompt | Value |
|---|---|
| Subsystem | QSYSWRK |
| Library | QSYS |
| Program | QTMSSRCP |
| Library | QTCP |
| Start jobs | *SAME |
| Initial number of jobs | 4 |
| Threshold | 2 |
| Additional number of jobs | 2 |
| Maximum number of jobs | 20 |
These values guarantee that the system starts four prestart jobs, starts two additional jobs when the available jobs fall below two, and allows a maximum of twenty prestart jobs.