linux-kernel - Re: [RFC 00/14] Dynamic Kernel Stacks

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Message-ID: <CA+CK2bAuH80JhTR9X6cbcHA3xH01sTXeDQBnXO_rUDGak-c+iw@mail.gmail.com>
Date: Mon, 18 Mar 2024 13:37:29 -0400
From: Pasha Tatashin <pasha.tatashin@...een.com>
To: David Laight <David.Laight@...lab.com>
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Subject: Re: [RFC 00/14] Dynamic Kernel Stacks

> > Perhaps a 'garbage collection' activity that reclaims stack
> > pages from processes that have been asleep 'for a while' or
> > haven't used a lot of stack recently (if hw 'page accessed'
> > bit can be used) might make more sense.

Interesting approach: if we take the original Andy's suggestion of
using an access bit to know which stack pages were never used during
context switch and unmap them, and as an extra optimization have a
"garbage collector" that unmaps stacks in some long sleeping rarely
used threads.  I will think about this.

Thanks,
Pasha