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From: dudek@utai.UUCP (Gregory Dudek)
Newsgroups: net.micro.mac
Subject: Re: Re: Mac Cache
Message-ID: <2052@utai.UUCP>
Date: Wed, 30-Jul-86 14:02:38 EDT
Article-I.D.: utai.2052
Posted: Wed Jul 30 14:02:38 1986
Date-Received: Wed, 30-Jul-86 14:43:23 EDT
References: <932@hounx.UUCP> <842@wang.UUCP> <2017@calmasd.CALMA.UUCP> <394@aecom.UUCP>
Reply-To: dudek@utai.UUCP (Gregory Dudek)
Organization: CSRI, University of Toronto
Lines: 20
Summary: 


  I find it very hard to believe that the Cache could be designed
as dangerously as people have been suggesting.  I use mine all the time
and despite many crashes experienced while mucking around, have 
never seen any signs of corrupted disk blocks which might be due to
the cache.
  Can anybody from apple confirm or refute the serious allegations?
  As for the claim that disk I/O only seemed to take place when a file was
closed, wouldn't an obvious and safe design for the cache would be one that had 
write-through only for file-system information, and maybe the Desktop. 
If this is what's happening, couldn't it explain some of the observed
I/O activity.  i.e. a file's data blocks
don't get write-through so ordinary file capture doesn't seem to cause
immediate disk I/O.
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