Thanks everyone for your suggestions. I'll test some of these suggestions with the user and see what the results are.
I'm going to start with a PDSE test as I think that is the quickest thing to try. The parmlib is updated frequently so caching the directory with LLA probably isn't the best plan. As I understand the user's description of the job, they are using PROJCL to generate some kind of reporting that is expanding JCL and pulling in the parms from this PDS. ----- Original Message ----- From: "Kreiter IBM-Main" <[email protected]> To: [email protected] Sent: Thursday, April 28, 2016 8:32:56 AM Subject: PDS I/O Performance Improvement Hello, I'm looking for some suggestions on how to possibly improve I/O performance to a PDS. A user is running a job that is reading a large parmlib (through PROJCL I believe). I think the access is random rather than sequential. The parmlib has ~180,000 members is has an LRECL of 80/BLKSIZE of 27,920. The performance team has reviewed a found ~ 6ms response time to the volume that houses the PDS with most of the time being connect time. Thanks, Chuck ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
