I did a post on the dev list (links below) about getting greater performance using caching and compression. I thought folks here probably have some great experience in running websites and could suggest improvements or problems with the suggested configuration changes.
If you do have suggestions/comments please share them to make roundcube better.
http://lists.roundcube.net/mail-archive/dev/2009-04/0000102.html http://trac.roundcube.net/ticket/1485800
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