[gclist] When to collect.
Thu, 20 Nov 1997 09:40:08 -0600 (CST)
On Thu, 20 Nov 1997, Ian Ringrose wrote:
> The other option we could make use of is a callback that is called just
> before a paged is paged out. If the page was in use by the cache, and not
> dirty, we could just discard it at that point. A GC could decide to copy
> all of it's live objects to a part filled page, so not having to paged it
> back in on the next GC pass.
This strikes me as being potientially very dangerous- consider the case
where the call back wants to copy the few remaining objects to a page
already paged out. Or the case where that particular part of the garbage
collector code has already been paged out. Such a handler would not dare
> I also get hit by the fact that if I discard a object in the cache that has
> not been used for a long time, the page is marked by the OS as being
> one to keep in RAM as I have just accessed it
This is better handled by providing some "discard page without touching
it" call. Not sure what the semantics here would be.
> Ian Ringrose