If you read a larger number of bytes into core let’s say above the bar less I/o should speed things up no ?
> On Mar 7, 2021, at 10:40 AM, Radoslaw Skorupka <[email protected]> wrote: > > W dniu 06.03.2021 o 16:50, Laddie Hanus pisze: >> LBI is available on DASD the largest block that will fit on 1 track, on the >> 3390 thats about 56K. Logical record (LRECL) is still limited to 32760, This >> is for new datasets being written. Existing datasets will read one block per >> i/o and will be no larger than what written. this is for BSAM read/check. >> manual DF/DSS Advanced services under the DEVTYPE macro will has a table of >> largest blocksize per decice type > > The problem is I have never seen LBI block on DASD. > Can I allocate such dataset using ISPF 3.2 or JCL DD ? > Can I copy existing LBI dataset using IEBGENER or IDCAMS? > > It's more or less like long member names in PDSE. They exist, however I > haven't found any. > And I think it is not only my observation. > > From the other hand large blocks on tape are widely used and supported by > existing system tools. > > Last, but not least: author of the thread wants better performance. I would > not expect significant performance improvement by changing BLKSIZE =half > track to whole track. > > -- > Radoslaw Skorupka > (looking for new job) > Lodz, Poland > > ---------------------------------------------------------------------- > 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
