On Tue, 27 Oct 2020 21:39:11 +1100, Andrew Rowley wrote: > >OMVS can produce a lot of SMF records. I did some testing on a short >shell script, and 1000 iterations of a loop produced about 28,000 type >30 records - around 200 records/second. The good news is that the >records are likely small with very similar data, so the facilities to >compress SMF data should handle it nicely. > >I wrote up the testing here, and it gives some idea of when separate >address spaces are used and SMF records written: >https://www.blackhillsoftware.com/news/2019/08/27/comparing-bash-and-bin-sh-on-z-os/ > Interesting.
But since OMVS manages address spaces by highwater mark, calling BPXAS only when the level rises and reaping after 30 seconds (is this configurable?) I'd expect orders of magnitude fewer SMF 30 than you observed. Perhaps /bin/sh has more builtins than bash, and is otherwise tuned to z/OS. It would be interesting to measure the effect of _BPX_SHAREAS. (Pro tip: I use ": >>broken/$f" rather than "touch broken/$f" when I create a file but don't need to update its timestamp. Fewer forks; fewer keystrokes.) -- gil ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
