neese@adaptx1.UUCP (01/04/91)
>/* ---------- "Seagate/CDC drive caches" ---------- */ > >Is there any difference between the Wren-6 (94191) and Wren-7 caching >schemes? On quick check of the manuals, Id say no, other than the >size (32k vs 240k). Does the wren-7 or any other seagate drive >do any sort of segmented caching? There is a substantial difference. In all previous versions of the CDC cache implementation the cache was strictly a read ahead type, where data requested behind the pointer in the cache caused a cache miss. In the Wren VII, there are many levels of firmware. Some are SCSI-1 and use the same older prefetch only algorithm. The newer SCSI-2 versions of the drive have a segmented, min/max prefetch, and true cache algorithm. Roy Neese Adaptec Senior SCSI Applications Engineer UUCP @ neese@adaptex uunet!cs.utexas.edu!utacfd! {nominil,merch,cpe}!adaptex!neese uunet!mlite!adaptex!neese