SFTP GET of data caused poor responses in on-line transaction processing
SFTP GET of data caused poor responses in on-line transaction processing
We have a number of Co:Z SFTP GET jobs running on the mainframe that have been scheduled since 08/2014 with approx. similar volumes, circa 2Gb each. Yesterday it appears three jobs ran con-currently albeit across 2 Mainframes and they caused a slow down of online transactions for their duration. Pretty sure it's not CPU / Mainframe Capacity related, the jobs have a lower priority than online and there's no obvious enqueues. There are 4 x 1Gb OSA cards per LPAR. Any advice on where to look to track the issue down?
Re: SFTP GET of data caused poor responses in on-line transaction processing
Assuming that z/OS starts the Co:Z sftp connection, there will be two address spaces:
1) The JES batch address spaces, which will run COZBATCH, the Unix Shell, and the cozsftp command
2) The OMVS address space which will runs the IBM OpenSSH "/bin/ssh" program
The latter normally accounts for 90% of the CPU time.
So, first I would check the related OMVS address space CPU usage, as these run in their own WLM service class.
Have you tuned IBM Ported Tools OpenSSH to exploit ICSF for crypto?
See the appropriate "Quick Install" guide for your release here: http://dovetail.com/docs/coz/coz_index.html
If you haven't done this, you can typically save 50% of the overall CPU time by following these steps.
If you are interested in additional assistance with tuning your system, you may wish to consider our Enterprise LIcense and Support agreements. Please send us an email at info@dovetai.com if you would like more information.
1) The JES batch address spaces, which will run COZBATCH, the Unix Shell, and the cozsftp command
2) The OMVS address space which will runs the IBM OpenSSH "/bin/ssh" program
The latter normally accounts for 90% of the CPU time.
So, first I would check the related OMVS address space CPU usage, as these run in their own WLM service class.
Have you tuned IBM Ported Tools OpenSSH to exploit ICSF for crypto?
See the appropriate "Quick Install" guide for your release here: http://dovetail.com/docs/coz/coz_index.html
If you haven't done this, you can typically save 50% of the overall CPU time by following these steps.
If you are interested in additional assistance with tuning your system, you may wish to consider our Enterprise LIcense and Support agreements. Please send us an email at info@dovetai.com if you would like more information.