Subject: Re: kernel map entry merging and PR 24039
To: YAMAMOTO Takashi <>
From: Andrew Brown <>
List: tech-kern
Date: 11/30/2004 21:25:48
On Wed, Dec 01, 2004 at 07:04:00AM +0900, YAMAMOTO Takashi wrote:
>> >i still think disabling entry merging (or, not to free memory for
>> >merged entries, at least) is a "real" fix because it's a design flaw
>> >to require memory allocation to free memory.
>> you can call it a design flaw if you want to, but imho it's more of a
>> flaw to consume more memory up front simply so that you don't have to
>> allocate it later.
>reserving memory for later use is a common practice.
>it's far better than relying upon pure luck.

reserving memory is fine.

rampantly allocating map entries (which happens when merging is
disabled) so that you'll never need to allocate a new one in order to
free is not quite the same thing.

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