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GC, ZMail

> [ I question why I seem to loose mem when I GC ]

	David L. Andre at JASPER.SCRC.Symbolics replies:

>	It is a longstanding bug in the address-space calculations for GC that
>	migration of modified pages from the load file to the paging file is not
>	included in the calculation of how much memory will be used up by GC.
>	This is the phenomenon you're observing.  If you (can) do a second GC,
>	you'll notice that the free space remains the same.  Alternatively, if
>	you netboot, everything is in the paging file initially, so you won't
>	observe the free-space shrinkage there, either.

	The fix is not easy, but not particularly difficult.  It hasn't been
	fixed yet mainly because we're concentrating on other things.

I say to that:

	Alright...let me rephrase the Q.

	When I GC, the info I get when I do a Show GC Status tells me that I
	LOST memory by doing the GC.  I ran NO user programs while GC was

	Which of the following happened:

		a) I really DID loose mem through some bug or feature in GC...

		b) I actually got more mem, but the updated info was not passed
		   on to the table used by the Show GC Status command, so it reports
		   (erroneously) that there is less mem left.

	I just want to clear this up in my mind...I'll probably end up leaving GC
	off and rebooting occasionally....


  | Michael Reed                     !allegra----                  |
  | mkr@philabs.philips.com                      \                 |
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