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Subject: Re: [patch 21/21] slab defrag: Obsolete SLAB
From: Matt Mackall <mpm@selenic.com>
To: Christoph Lameter <clameter@sgi.com>
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Date: Wed, 14 May 2008 14:49:23 -0500
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On Wed, 2008-05-14 at 12:21 -0700, Christoph Lameter wrote:
> On Wed, 14 May 2008, Matt Mackall wrote:
> 
> > > Interrupt exit in general would have to inspect the per cpu structures of 
> > > all slab caches on the system?
> > 
> > Why's that? When we're not under pressure (fast path), we can delay (and
> > batch) remote frees. When we are under pressure (slow path), we can do
> > everything immediately.
> 
> Fastpath is what? I guess slow path means we called into the page 
> allocator?

No, slow path here means we're already under memory pressure, so we
don't care if something takes longer if it saves memory.

-- 
Mathematics is the supreme nostalgia of our time.