From owner-freebsd-hackers@FreeBSD.ORG  Thu Nov  3 14:57:46 2005
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Date: Thu, 3 Nov 2005 16:57:29 +0200
From: Giorgos Keramidas <keramida@linux.gr>
To: kamal kc <kamal_ckk@yahoo.com>
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References: <20051103023936.63209.qmail@web35704.mail.mud.yahoo.com>
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Cc: freebsd <freebsd-net@freebsd.org>, freebsd <freebsd-hackers@freebsd.org>
Subject: Re: allocating 14KB memory per packet compression/decompression
	results in vm_fault
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On 2005-11-02 18:39, kamal kc <kamal_ckk@yahoo.com> wrote:
> dear everybody,
>
> i am trying to compress/decompress ip packets.
> for this i have implemented the adaptive lzw compression.
> i put the code in the ip_output.c and do my compression/decompression
> just before the if_output() function call so that i won't interfere with
> the ip processing of the kernel.
>
> for my compression/decompression i use string tables and temporary
>  buffers which take about 14KB of memory per packet.

If you're allocating 14 KB of data just to send (approximately) 1.4 KB
and then you throw away the 14 KB immediately, it sounds terrible.