PC hardware shouldn't be the problem, since z/OS is reporting 3 million EXCPs. That's a lot of I/O.
Could it be that you REWRITE with a different record length and COBOL has to shift the whole file? Perhaps a GTF trace will help you figure out what is happening. You might do better to write a third file, rather than REWRITE the whole file. Then either rename the third file or copy it back over the INFILE. It would provide better recovery in the event of an abend, as well. Good luck, Tom Marchant On Sat, 26 Aug 2006 18:47:38 +0800, Johnny Luo <[EMAIL PROTECTED]> wrote: >Hi, > >I don't know whether this is really a 'performance issue' because it occurs >on >our company's ADCD ZOS1.4 system running on an pc. > >We recently converted some pl/i batch programs to cobol for a customer. >(Enterprise Z/os PL/I 3.1) Then they sent us with some input data sets >for testing purpose so we need to run original PL/I programs using these >data sets first. > >Most of programs just run quickly (two or three minutes on ADCD system) >until we encounter one which REWRITE a sequtial file. > >The input are two sequtial data set with (PS, VB, LRECL=1024, BLKSIZE=27998) >and the program logic is simple: just read two files and if needed rewrite >one file. > >First file has 50,000 records and second has 100,000 records. If I remove >the >REWRITE statement the program will finish in three minutes. However, if with > >REWRITE added, it will run for more than an hour. > >And this is not the only one. After this step, there is another similar >program and >at this time the program has run for nine hours and we don't know when it'll >finish. > >Since our company doesn't own a 'real' z machine so we have to finish our >testing >on ADCD system. I've tried some methods to improve the performance but they >just won't work. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
