May 10, 2012

IIS 7.5 – different file size for same compressed file served from two different servers


I’m facing the problem that our lengthy CSS file (129 KB) gets delivered by our ASP.NET web app (running on IIS 7.5 using .NET 4.0) compressed to 24 KB on my local server machine and 36 KB on both our staging and production sites. My local OS is Windows Server 2008 R2 Enterprise, the web servers run Windows Web Server 2008 R2.

I used the Fiddler to look into the requests but they seem not to differ in anything important, i.e. Accept-Encoding: gzip, deflate is sent to all servers and all reply with Content-Encoding: gzip. All have static and dynamic compression enabled.

Does anybody have any idea what could be causing the difference in behavior?

Asked by Oliver


Check out Scott Forsyth’s blog entry on compression… it’s a great one. Most importantly, there are several compression levels that can be set and may be different between your servers. You can check out more at the site on httpCompression.


Answered by Chris Anton

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