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Re: [patch] Avoid the use of mmap as buffer for stdio streams

From: Arjan van de Ven <arjan at linux dot intel dot com>
To: Wolfram Gloger <wmglo at dent dot med dot uni-muenchen dot de>
Cc: libc-alpha at sourceware dot org
Date: Sat, 25 Nov 2006 19:45:19 +0100
Subject: Re: [patch] Avoid the use of mmap as buffer for stdio streams
References: <4566DE80.7050207@linux.intel.com> <20061125184012.4312.qmail@md.dent.med.uni-muenchen.de>

Wolfram Gloger wrote:

Although I think "custom mallocs not providing calloc()" is by now
probably not a very strong argument, the fact that zeroed memory is
required somewhat weakens the disadvantages of using mmap.

actually... mmap means the kernel needs to zero 4Kb of memory (and it does)... even though the buffer is only 1Kb by default... so that's 3Kb extra zeroed for no reason ...

(this is part of why mmap is so expensive)

References:
- [patch] Avoid the use of mmap as buffer for stdio streams
  - From: Arjan van de Ven
- Re: [patch] Avoid the use of mmap as buffer for stdio streams
  - From: Wolfram Gloger

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