On Sun, 2 May 2010 14:15:48 +0000, john gilmore wrote: >IBM is right. > >BLKSIZE=32760 is the maximal signed integer value that is 1) not greater than >the capacity of a halfword (usually required to avoid control block overflow) >and 2) a multiple of 8, 32760 = 4096 x 8 (required for doubleword buffer >alignment). > Errr... 4095 x 8 ?
But why? Does channel hardware require that both ends of the buffer be aligned? If 32759 works, why not 32767? Is there a performance value to alignment? I believe the CCW allows up to 65535. -- gil ---------------------------------------------------------------------- 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
