Thanks so much for the tip
> On Feb 3, 2017, at 2:42 PM, Farley, Peter x23353 > <[email protected]> wrote: > > BSAM only gets you an entire block on a READ. You have to extract each > varying record from the block with your own code. > > On a WRITE you have to give it an entire block, BDW + one or more RDW + > record. You have to construct the block yourself in your own code before you > issue the WRITE. > > OTOH you don't have to wait for completion of a READ or a WRITE. You can > issue a WRITE at the end of a processing loop and then go back to process the > next record while the WRITE completes, and only CHECK the WRITE when you are > ready to issue the next WRITE. > > Similarly for READ's, issue another READ right after the start of processing > for the prior record, then CHECK the second READ when you come back to the > top of the processing loop. > > Complicated, but it can provide improved (FSVO improved) elapsed time by > overlapping processing with I/O rather than processing synchronously. > > HTH > > Peter > > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[email protected]] On > Behalf Of Joseph Reichman > Sent: Friday, February 03, 2017 2:27 PM > To: [email protected] > Subject: Re: BSAM vs QSAM > > I have huge VB files > > Don't really understand what you mean by > > Deblock after doing a READ then WAIT > > Where an entire block is read subsequent READs > Just point to the next record > >> On Feb 3, 2017, at 2:22 PM, Blaicher, Christopher Y. >> <[email protected]> wrote: >> >> There can be if you code for just what you expect. >> >> QSAM does multi-buffer I/O for you, with BSAM you have to issue multiple >> WRITE or REAAD commands and do a WAIT, not to mention having to block or >> de-block the buffer, which can be a real pain for VBS files. >> >> It really depends on how much you are processing and how often you are doing >> it to determine if the amount of time you are going to spend on developing >> it makes it worth it. >> >> Using QSAM with GET LOCATE (as long as you aren't processing VBS files) and >> a reasonable BUFNO of 10 or more is going to get you close to most BSAM >> applications. GET or PUT with the MOVE option is the easiest to code for. >> >> Chris Blaicher >> Technical Architect >> Mainframe Development >> Syncsort Incorporated >> 2 Blue Hill Plaza #1563, Pearl River, NY 10965 >> >> P: 201-930-8234 | M: 512-627-3803 >> E: [email protected] >> >> www.syncsort.com >> >> CONNECTING BIG IRON TO BIG DATA >> >> >> -----Original Message----- >> From: IBM Mainframe Discussion List [mailto:[email protected]] On >> Behalf Of Joseph Reichman >> Sent: Friday, February 3, 2017 1:51 PM >> To: [email protected] >> Subject: BSAM vs QSAM >> >> Hi >> >> BSAM is a bit more complex than QSAM >> >> Is there any performance improvement >> >> Thanks > -- > > This message and any attachments are intended only for the use of the > addressee and may contain information that is privileged and confidential. If > the reader of the message is not the intended recipient or an authorized > representative of the intended recipient, you are hereby notified that any > dissemination of this communication is strictly prohibited. If you have > received this communication in error, please notify us immediately by e-mail > and delete the message and any attachments from your system. > > ---------------------------------------------------------------------- > 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
