Should I be using Gzip or output caching ?

Hi,


I have a website with approx. 50.000 visitors a month. I have played a bit with output caching and  gzip compression (compression is done with this module http://madskristensen.net/post/HTTP-compression-in-ASPNET-20.aspx). Now it seems the two are interfering with each other. When I use a substitution-control to punch a hole in the cache, it doesn't work unless I disable the gzip compression.


My question is now. Which one should I use - compression or output caching (or both). If I should use both, does anyone have any idea why they interfere with each other?


thanks
Thomas
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