Subject: Re: change in gathering of kernel memory stats
To: Dennis Ferguson <email@example.com>
From: Jason Thorpe <firstname.lastname@example.org>
Date: 02/02/1997 14:25:59
On Sun, 02 Feb 1997 14:22:17 -0800
Dennis Ferguson <email@example.com> wrote:
> The use of free() is not a hardship at all, actually, since if you measure
> it you'll find the savings from using FREE() are miniscule (it isn't called
> that often in any case, and the overhead of a function call just isn't
> that large compared to the work it does). MALLOC() does save you a worth
> while amount of work in the particular case that the size of the structure
> you are allocating is a compile-time constant, but probably isn't used enough
> to make the use of malloc() too disadvantageous for an lkm.
The one place where this can bite you is with LKMs that do any sort
of mbuf allocation... MGET() contains a call to MALLOC().
Perhaps a global (maybe "do_kmemstats"?) would be good, so that a fairly
cheap runtime test can be made inside the MALLOC() and FREE() macros.
Jason R. Thorpe firstname.lastname@example.org
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