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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 13:18:32 -0500
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On Wed, 2008-05-14 at 11:03 -0700, Christoph Lameter wrote:
> > What is the big problem of having a batched free queue? If the expiry
> > is done at a good bounded time (e.g. on interrupt exit or similar)
> > locally on the CPU it shouldn't be a big issue, should it?
> 
> 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.

-- 
Mathematics is the supreme nostalgia of our time.