vm370 used 101 byte filler records on 3330 drives for page formated
stuff (paging, spool, chkpt, directory, etc). 3330 had 3 4k page records
per track with 101 byte filler records between the page records ... 57
4k page records per cylinder.
I have a vague memory of a similar technique on page datasets, probably
early MVS or SVS. Rather than filler records between records, it put a
variable size filler record as record 1 on the track. first track in
a cylinder had a small filler or no filler, second track had a smaller
filler, third track had a slightly larger filler, etc, to the end of the
cylinder.
It was for the same reason, it allowed a paging operation to access a
record on one track, switch heads and access the next record on higher
track in the same cylinder, without losing a rotation.
--
Bruce A. Black
Senior Software Developer for FDR
Innovation Data Processing 973-890-7300
personal: [EMAIL PROTECTED]
sales info: [EMAIL PROTECTED]
tech support: [EMAIL PROTECTED]
web: www.innovationdp.fdr.com
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