Re: SDB (optimal?) BLKSIZE on tape device

2011-07-21 Thread R.S.
That's also my understanding, but SDB had chosen blocksize which is not the largest possible. That raises my doubts. -- Radoslaw Skorupka Lodz, Poland W dniu 2011-07-21 06:38, Mike Schwab pisze: Tapes are pretty linear. The larger the blocksize, the fewer the blocks to write. And each

Re: SDB (optimal?) BLKSIZE on tape device

2011-07-21 Thread R.S.
W dniu 2011-07-21 16:04, Yifat Oren pisze: Hi Radoslaw, In Using Data Sets it says that the optimum BLKSIZE for 3590 is: 262 144 (256 KB) except on some older models on which it is 229 376 (224 KB) .. Your device seems to fall into the 2nd category for some (wrong?) reason.. This is

Re: SDB (optimal?) BLKSIZE on tape device

2011-07-21 Thread Yifat Oren
Discussion List [mailto:IBM-MAIN@bama.ua.edu] On Behalf Of R.S. Sent: יום ד 20 יולי 2011 17:03 To: IBM-MAIN@bama.ua.edu Subject: SDB (optimal?) BLKSIZE on tape device (SDB - System Determined Blocksize) I just coded LRECL=80,BLKSIZE=0,BLKSZLIM=2G on MDL tape device in 3590 mode. I noticed something

SDB (optimal?) BLKSIZE on tape device

2011-07-20 Thread R.S.
(SDB - System Determined Blocksize) I just coded LRECL=80,BLKSIZE=0,BLKSZLIM=2G on MDL tape device in 3590 mode. I noticed something strange for me: SDB was 229360B, but it's NOT the largest block available! The device also accepted BLKSIZE=262080 (the largest multiple of 80 less than

Re: SDB (optimal?) BLKSIZE on tape device

2011-07-20 Thread Mike Schwab
Tapes are pretty linear. The larger the blocksize, the fewer the blocks to write. And each block has a bit of overhead to it. 2011/7/20 R.S. r.skoru...@bremultibank.com.pl: (SDB - System Determined Blocksize) I just coded LRECL=80,BLKSIZE=0,BLKSZLIM=2G on MDL tape device in 3590 mode. I