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Message-ID: <b0943d9e0610160144y2a432683s886c1a19b33a91ee@mail.gmail.com>
Date: Mon, 16 Oct 2006 09:44:11 +0100
From: "Catalin Marinas" <catalin.marinas@gmail.com>
To: "Mike Galbraith" <efault@gmx.de>
Subject: Re: Major slab mem leak with 2.6.17 / GCC 4.1.1
Cc: "Pekka Enberg" <penberg@cs.helsinki.fi>,
       "nmeyers@vestmark.com" <nmeyers@vestmark.com>,
       linux-kernel@vger.kernel.org
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On 16/10/06, Mike Galbraith <efault@gmx.de> wrote:
> On Mon, 2006-10-16 at 09:07 +0100, Catalin Marinas wrote:
> > Kmemleak introduces some overhead but shouldn't be that bad.
> > DEBUG_SLAB also introduces an overhead by erasing the data in the
> > allocated blocks.
>
> 2.6.18 with your rc6 patch booted normally with stack unwind enabled.

The only difference is that kmemleak now uses save_stack_trace() to
generate the call chain. In the previous versions I implemented a
simple stack backtrace myself, with the disadvantage that it only
worked on ARM and x86.

I think kmemleak should use the common stack trace API and investigate
why it is slower (either save_stack_trace is slower with stack unwind
enabled or kmemleak doesn't use these functions properly).

-- 
Catalin