Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 14 Dec 1996 14:12:47 -0700 (MST)
From:      Terry Lambert <terry@lambert.org>
To:        phk@critter.tfs.com (Poul-Henning Kamp)
Cc:        dyson@freebsd.org, peter@spinner.dialix.com, smp@freebsd.org, haertel@ichips.intel.com
Subject:   Re: some questions concerning TLB shootdowns in FreeBSD
Message-ID:  <199612142112.OAA22198@phaeton.artisoft.com>
In-Reply-To: <5557.850593988@critter.tfs.com> from "Poul-Henning Kamp" at Dec 14, 96 09:06:28 pm

next in thread | previous in thread | raw e-mail | index | archive | help
> The crucial thing, as far as I can see, is to find out >if< we need to
> tell the other CPU's about this change to the pagetables.  For a 2cpu
> system the penalty of stopping the other CPU is still within bounds
> of the reasonable, but stopping three CPUs needlessly is not a good idea.
> 
> Is there any cheap way to keep a refcount (or bitmap) per vm-object so
> we can see if we need to kick the other CPUs if we fiddle it ?

Oh, I like this.

It would make it very easy to have multiple references in the UP case,
as well as the MP case.

This would let us do device/offset as well as vnode/offset based caching
(for instance, hanging all cache buffers for vnodes on a device off the
device vnode).

I've wanted this for some time, since I am determined that vclean must
die...


					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199612142112.OAA22198>