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Date: Thu, 12 Jun 2003 11:35:59 +0200
From: Steven Scholz <steven.scholz@imc-berlin.de>
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Subject: Re: Stopping the GC thread?
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David,

>>2.) What happnens when I send a SIGSTOP in the middle of a running GC?
>>Will it stop immediately? Or will it take a while?
> 
> 
> It'll finish copying the node it's _currently_ garbage-collecting, which
> may involve decompressing up to a page of data, recompressing it and
> writing it out elsewhere. It may also need to wait for erases to
> complete.
> 
> Even after it's stopped, if there are erasable blocks on the queue,
> they'll continue to be erased in the background by kupdated. You cannot
> prevent that.

But the impact on system performance done by kupdated is not as 
critical as the one that's done by the GC intself, is it?

> 
>>I suppose that a few more sectors will be examened and written... 
>>(10ms, 100ms, 1000ms ...???)
> 
> 
> 'sector'?  Read http://sources.redhat.com/jffs2/jffs2.pdf 
I meant flash sectors.

Steven