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 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 256kiB). > I thougth that the largest blocksize is the "optimal" one, and it's chosen > by the system. > BTW: I tested both blocksizes. The larger one (262080) tends to be faster. > > Any clue? > > -- > Radoslaw Skorupka > Lodz, Poland -- 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: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
