In <[EMAIL PROTECTED]>, on 08/02/2005
at 08:53 AM, Bill Fairchild <[EMAIL PROTECTED]> said:
>I don't know. That is an interesting question. Certainly the same
>need to serialize in order to protect data in the case of one writer
>and seven readers exists. Perhaps this situation didn't apply on
>the 3880-2305 because the only software component that ever used
>the multiple exposures on a 2305 was ASM (I think),
My recollection was that you automatically used a free exposure on the
2305 unless you explicitly specified an exposure. I don't know whether
that was true for the paging versions of the 3880.
>But on the 2305 there was no need for serialization at the control
>unit level, since the only user was ASM
No. The 2305 was supported for general use, not just paging.
>I would also guess that the 3880 caching controller models 11 and
>21, which were intended for paging I/O only, had the same
>situation [1], and I think multiple exposures were available for
>those devices as well.
They definitely had multiple exposures.
--
Shmuel (Seymour J.) Metz, SysProg and JOAT
ISO position; see <http://patriot.net/~shmuel/resume/brief.html>
We don't care. We don't have to care, we're Congress.
(S877: The Shut up and Eat Your spam act of 2003)
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