[jdev] Public Server with Compression Available

[Stephen Pendleton]

I can also confirm that it works well: I am seeing reductions of the XML
stream of about 60%. Does Wildfire have compression for s2s connections as
well as c2s?

Stephen

-----Original Message-----
From: jdev-bounces at jabber.org [mailto:jdev-bounces at jabber.org] On Behalf Of
JD Conley
Sent: Monday, January 09, 2006 9:12 PM
To: Jabber software development list
Subject: RE: [jdev] Public Server with Compression Available


I thought I'd fire off a little update. I've heard from four different
client project developers. They were all able to get zlib based compression
working with only a few little stumbling blocks. There are some truly
impressive compression ratios being generated over time! I'll let them
divulge that information, though.

Here were some of our stumbling blocks:

1) If you have control over the zlib header and checksum footer for DEFLATE
(only supported by some libraries) you need to make sure you include them.

2) Make sure you flush your deflater instance so it completely compresses
the input buffer. If you're using the reference implementation
(http://www.zlib.net/) this is done by passing a Z_SYNC_FLUSH. You don't
want to do a Z_FINISH, as you should preserve the dictionary for the entire
XMPP stream for better compression.

3) Keep an instance of your inflater and deflater around for each socket
connection.

4) Don't assume that one read from a socket will yield you something that
can be inflated. Also don't assume once you get an inflated buffer that it
will be a stanza.

If anybody else wants to test on beta.soapbox.net, feel free. The server is
still running (and has S2S enabled now).

-JD Conley