Path: utzoo!attcan!uunet!husc6!rutgers!njin!princeton!phoenix!caromero
From: caromero@phoenix.Princeton.EDU (C. Antonio Romero)
Newsgroups: comp.sys.next
Subject: Re: Number of writes on an optifloppy
Message-ID: <4434@phoenix.Princeton.EDU>
Date: 14 Nov 88 17:32:04 GMT
References: <8646@spl1.UUCP> <568@poseidon.ATT.COM> <7377@pasteur.Berkeley.EDU>
Reply-To: caromero@phoenix.Princeton.EDU (C. Antonio Romero)
Organization: Princeton University, NJ
Lines: 31

In article <7377@pasteur.Berkeley.EDU> korn@eris.berkeley.edu (Peter "Arrgh" Korn) writes:
>In <568@poseidon.ATT.COM>, ech@poseidon.ATT.COM (Edward C Horvath) said:  
>>From article <8646@spl1.UUCP>, by sarge@metapsy.UUCP (Sarge Gerbode):
>>> What I'm curious about is -- is there any limit to the number of
>>> writes one could reasonably expect to be able to perform on an
>>> optifloppy?...
>>[Ed got a back of the envelope figure from a Sony type of 1-10M writes...]
>????  This is considered enough?
>[Pete estimates the heavy swapping would exhaust 10M writes in 6 to
sixty days...]
>That's not a very reassuring.

A couple of things:

	o I saw an article in either InfoWorld or MacWeek last week
	  (sorry, can't find it now) which claimed that manufacturers 
	  had run a drive doing continuous read/write cycles for three
	  months without failure.  Not too sure if this was the NeXT's
	  drive, but I think the media are pretty similar...

	o You're assuming all these writes are done to a fixed portion
	  of the disk.  I had the impression that Mach doesn't do its
	  swapping from/to reserved swap space, but rather uses a file.
	  (I'm not sure on this...) This would probably extend life
	  somewhat.  

	o I doubt people would even try to bring something to market 
	  if it was as unreliable as this... Think about it.  Would it
	  make sense for Jobs, or anyone else, to gamble this way?

-Antonio Romero    romero@confidence.princeton.edu