Re: Questions regarding SMS compacted dataset
Victor, Are you using DFDSS DUMP or COPY? The DUMP function will _not_ decompress the data set and will take a physical copy of it. Naturally, as it is already compressed, further compression when copying it to tape will not be very beneficial. Other utilities, such as IEBGENER. have to decompress the data set as they are doing a record by record, logical, copy (this may not be true for IDCAMS when using the compression interface, see II14507). Hope that helps, Yifat -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Victor Zhang Sent: Tuesday, April 10, 2012 6:01 PM To: IBM-MAIN@bama.ua.edu Subject: Re: Questions regarding SMS compacted dataset Chris, Thanks for the reply. Using dss is to back extended files to tape/virtual tape. Your answer said the data read will be expanded. So even by setting compact as N, the amount of data written to tape/virtual tape will be same, right? My another question is: If I set compact=N for storage class, so data sets will not be compressed/compacted. If I use same utility to copy it to tape/virtual tape, will there any difference for the data stream writing to tape? I already noticed a difference: By enabling compact option in storage class, I have very low compression ratio for data written to tape/virtual tape, do you have any idea? Regards Victor -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Questions regarding SMS compacted dataset
Yifat, Thank you very much, very help. One more question: Does both physical dump and logical dump NOT decompress extended compacted PS dataset OR Does physical dump NOT decompress extended compacted PS dataset OR Does copy decompress extended compacted PS dataset? Regards Victor -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Questions regarding SMS compacted dataset
On Wed, 11 Apr 2012 12:53:22 +0300, Yifat Oren wrote: Other utilities, such as IEBGENER. have to decompress the data set as they are doing a record by record, logical, copy (this may not be true for IDCAMS when using the compression interface, see II14507). Is this done by the utility (ugh!) or by the access method? -- gil -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Questions regarding SMS compacted dataset
Access method snip Other utilities, such as IEBGENER. have to decompress the data set as they are doing a record by record, logical, copy (this may not be true for IDCAMS when using the compression interface, see II14507). Is this done by the utility (ugh!) or by the access method? /snip -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Questions regarding SMS compacted dataset
Victor, Logical dump of compressed format data sets does not decompress them. This quote from the DFSMSdss Storage Administration sort-of implies that: 1. The COMPRESS keyword is ignored if it is specified during a logical data set dump for either compressed-format sequential data sets or compressed-format VSAM data sets. (The COMPRESS keyword specifies that DFSMSdss should compress the output dump data set before writing it to output medium - so, double compression is being avoided here). COPY must decompress an extended-format compressed data set when copying it to a basic-format data set (on tape). Best Regards, Yifat -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Victor Zhang Sent: Wednesday, April 11, 2012 3:52 PM To: IBM-MAIN@bama.ua.edu Subject: Re: Questions regarding SMS compacted dataset Yifat, Thank you very much, very help. One more question: Does both physical dump and logical dump NOT decompress extended compacted PS dataset OR Does physical dump NOT decompress extended compacted PS dataset OR Does copy decompress extended compacted PS dataset? Regards Victor -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Questions regarding SMS compacted dataset
Having never used ADRDSSU, I can't say for sure, but it would be a pretty bad utility if when it was done it did not leave a good readable copy of the data set. It should either do it right or tell you why it can't. If you are copying a file from a SMS to a non-SMS volume, then it should write the expanded file on the destination volume or tell you that it can't do that copy or move function. Doing a move and leaving the data unreadable would be ample justification for opening an APAR. IEBGENER and most other products that I know of use the BSAM or QSAM access methods when dealing with a compressed file. The SAM access methods return expanded records to the application, or in the case of writing, compress the data on the way out. Chris Blaicher Senior Software Engineer, Software Services Syncsort Incorporated 50 Tice Boulevard, Woodcliff Lake, NJ 07677 P: 201-930-8260 | M: 512-627-3803 E: cblaic...@syncsort.com www.syncsort.com Check out our Knowledge Base at www.syncsort.com/support Syncsort aims for the best product and service experience. We welcome your feedback. -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of Victor Zhang Sent: Monday, April 09, 2012 11:46 PM To: MVS List Server 1 Subject: Re: Questions regarding SMS compacted dataset Hi all, Sorry, forgot to mention is if the program trying to read compressed extended physical sequential file is ADRDSSU, will only compressed data be returned? How about IEBGEN program? Regards Victor -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Questions regarding SMS compacted dataset
Chris, Thanks for the reply. Using dss is to back extended files to tape/virtual tape. Your answer said the data read will be expanded. So even by setting compact as N, the amount of data written to tape/virtual tape will be same, right? My another question is: If I set compact=N for storage class, so data sets will not be compressed/compacted. If I use same utility to copy it to tape/virtual tape, will there any difference for the data stream writing to tape? I already noticed a difference: By enabling compact option in storage class, I have very low compression ratio for data written to tape/virtual tape, do you have any idea? Regards Victor -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Questions regarding SMS compacted dataset
On Tue, Apr 10, 2012 at 10:00 AM, Victor Zhang victor_wor...@yahoo.com.cn wrote: deleted I already noticed a difference: By enabling compact option in storage class, I have very low compression ratio for data written to tape/virtual tape, do you have any idea? Regards Victor You are sending compressed data, You can't compress it anymore. -- Mike A Schwab, Springfield IL USA Where do Forest Rangers go to get away from it all? -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Questions regarding SMS compacted dataset
In each case when you copy dataset from DASD to TAPE ar vice versa, the data in transit are uncompressed. Compression/lack of compression on source/target doesn't matter. -- Radoslaw Skorupka Lodz, Poland W dniu 2012-04-10 17:00, Victor Zhang pisze: Chris, Thanks for the reply. Using dss is to back extended files to tape/virtual tape. Your answer said the data read will be expanded. So even by setting compact as N, the amount of data written to tape/virtual tape will be same, right? My another question is: If I set compact=N for storage class, so data sets will not be compressed/compacted. If I use same utility to copy it to tape/virtual tape, will there any difference for the data stream writing to tape? I already noticed a difference: By enabling compact option in storage class, I have very low compression ratio for data written to tape/virtual tape, do you have any idea? Regards Victor -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN -- Tre tej wiadomoci moe zawiera informacje prawnie chronione Banku przeznaczone wycznie do uytku subowego adresata. Odbiorc moe by jedynie jej adresat z wyczeniem dostpu osób trzecich. Jeeli nie jeste adresatem niniejszej wiadomoci lub pracownikiem upowanionym do jej przekazania adresatowi, informujemy, e jej rozpowszechnianie, kopiowanie, rozprowadzanie lub inne dziaanie o podobnym charakterze jest prawnie zabronione i moe by karalne. Jeeli otrzymae t wiadomo omykowo, prosimy niezwocznie zawiadomi nadawc wysyajc odpowied oraz trwale usun t wiadomo wczajc w to wszelkie jej kopie wydrukowane lub zapisane na dysku. This e-mail may contain legally privileged information of the Bank and is intended solely for business use of the addressee. This e-mail may only be received by the addressee and may not be disclosed to any third parties. If you are not the intended addressee of this e-mail or the employee authorised to forward it to the addressee, be advised that any dissemination, copying, distribution or any other similar activity is legally prohibited and may be punishable. If you received this e-mail by mistake please advise the sender immediately by using the reply facility in your e-mail software and delete permanently this e-mail including any copies of it either printed or saved to hard drive. BRE Bank SA, 00-950 Warszawa, ul. Senatorska 18, tel. +48 (22) 829 00 00, fax +48 (22) 829 00 33, www.brebank.pl, e-mail: i...@brebank.pl Sd Rejonowy dla m. st. Warszawy XII Wydzia Gospodarczy Krajowego Rejestru Sdowego, nr rejestru przedsibiorców KRS 025237, NIP: 526-021-50-88. Wedug stanu na dzie 01.01.2012 r. kapita zakadowy BRE Banku SA (w caoci wpacony) wynosi 168.410.984 zotych. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
Re: Questions regarding SMS compacted dataset
Hi all, Sorry, forgot to mention is if the program trying to read compressed extended physical sequential file is ADRDSSU, will only compressed data be returned? How about IEBGEN program? Regards Victor -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@bama.ua.edu with the message: INFO IBM-MAIN
