I had ever been thinking SMS compression was a dictionary-less algorithm and something in the zEDC announce and availabity seems to lead to this point.
I'm sorry but I wasn't able to find out more infos on DFSMS compression way to work. Regards. Massimo 2015-05-07 12:34 GMT+02:00 Massimo Biancucci <[email protected]>: > I'm sure VTS does compress data even though I think it's a hardware > feature and at application level (zOS channel program I mean) there's no > difference in terms of EXCP. In the worst case we could expect a bigger > connect time anyway VTS is faster than SMS compressed DASD despite of the > number of EXCPs. > > Regards. > Massimo > > 2015-05-05 17:07 GMT+02:00 Elardus Engelbrecht < > [email protected]>: > >> Massimo Biancucci wrote: >> >> >Output - Compressed Dataset >> >STEPNAME PROCSTEP RC EXCP CPU SRB CLOCK SERV PG PAGE >> SWAP >> > ST040 00 1247K 8.65 .79 23.77 38592K 0 0 >> 0 >> >> >Output - DUMMY >> >STEPNAME PROCSTEP RC EXCP CPU SRB CLOCK SERV PG PAGE >> SWAP >> > ST040 00 201K 1.10 .04 2.24 4725K 0 0 >> 0 >> >> >Output - Virtual Tape Dataset >> >STEPNAME PROCSTEP RC EXCP CPU SRB CLOCK SERV PG PAGE >> SWAP >> > ST040 00 3730K 1.19 .20 8.86 7476K 0 0 >> 0 >> >> >What is not so clear to me is why the elapsed time does grow so much >> even though there's no CPU constraint. >> >> >Because of the lower number of EXPCs I'd been expecting something less >> in terms of elapsed or something similar. >> >> VTS has more EXCP. Wild guess - Does your VTS do hardware compression >> despite your software compression? >> >> Groete / Greetings >> Elardus Engelbrecht >> >> ---------------------------------------------------------------------- >> 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
