Steve, There's just one fly in the ointment that I'd like to point out ... If you create *one* file containing *multiple* email messages and send it to SYSOUT=(B,SMTP) ... I mean, yes, it'll work, but it'll tie up the SMTP task and cause performance problems if your SMTP task is busy with other emails, too. The SMTP task is a "single-minded" process. It performs only one action at a time. While busy reading a file from SPOOL, SMTP will take this file apart and store each email message that it contains on disk in 2 files (1 address book and 1 message contents file). Only after all email messages contained in this one SPOOL file are stored, will SMTP continue with its other duties, such as listening on the network for incoming emails, or sending one of the stored emails).
In my experience with a relatively busy M/F site posting hundreds of individual emails per day (some of them time-critical pager event notifications), liberally sprinkled with "mass-mails" (single SPOOL files containing anywhere from 10 up to 3,000 email messages), I have to say that SMTP performance was greatly improved once I broke those mass-mails into individual SPOOL files containing only one email per file. A mass-mail SPOOL file containing 3,000 emails took several hours to be read in and stored as disk files on the busy M/F. Meanwhile, nothing else happened in SMTP ... not a single stored email was sent, no emails were received, pager notifications did not go out in a timely manner, Operators got calls from users, Operators called me saying "SMTP is hung or worse, cancelled SMTP ... it was a mess. With one email message per SPOOL file, SMTP could process the emails in the way it was designed to do, in a round-robin fashion: read 1 email from SPOOL and store it, send one or more stored emails, receive incoming emails and store them, and so on. Additional improvements could be realized when I stored those mass-mail SPOOL files with a lower JES2 queue priority, thus allowing individual emails to go right ahead, in and out of the system in a few minutes without being delayed too much by the lower importance mass mail traffic. I urge you to change your process and use BPXWDYN to dynamically allocate and free one SPOOL file for each individual email message. Your SMTP mail task and your user community will thank you for that (or at least you won't have any complaints :-). Regards, Ulrich Krueger -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Steve Comstock Sent: Tuesday, March 17, 2009 09:47 To: [email protected] Subject: Re: FW: SYSOUT dynamic allocation in COBOL Steve Comstock wrote: <snipped> OK. Today I took some time and tested it. Works like a champ; it just wasn't clear on the original post that the intent was to go to SMTP. So I wrote some code that sends 10 records to each entry in a table of email addresses. The essential logic is: open mailout write email header records write 10 data records (get input data record, format write it out) - 10 times write email trailer records close mailout repeat that in a loop for each email addressee you have. No need for dynamic allocation. Happy to send the code to anyone who requests it. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
