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Date: Sat, 1 Nov 2008 19:08:43 -0500
From: "Biks N" <freebsd.dev@gmail.com>
To: freebsd-hackers@freebsd.org
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Subject: Need to optimize cutstom kernel hacks
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X-List-Received-Date: Sun, 02 Nov 2008 00:36:51 -0000

Hi,

To get started with FreeBSD kernel, I have been working on IP Packet
compression. After numerous crashes and failures now everything looks
good and stable. I am using kernel zlib routines to compress payload.

However I think my implementation is not efficient at all.

Here are the steps I am doing for compression:

1. copy Payload to empty buffer using m_copydata() function
2. call deflateInit2 () for deflate initialization
3. call deflate() for actual compression
4. copy the compressed data in buffer back to Payload


I have to go through all above 4 steps for each packet!

I think it will be lot faster and efficient if:
 * Somehow get away with deflateinit2() each time for each packet.
 * I can get to Payload pointer without using m_copydata() so that I
don't need to copy data back and forth.


Looking for your valuable suggestions and tips :)

Bikrant