Comments on: Asp.net & IIS Tricks:- Using GZip Compression with IIS 6.0 to compress your dynamic content such as your aspx pages and increase the client side experience by downloading the pages fast.

By: venkat

venkat — Fri, 19 Feb 2010 18:35:00 +0000

Hi,

This is artical is very nice and very helpfull to me.

after I set this I found an error
"Permission denied for to call method Location.toString on"

If you any idean about this please advice.

Thanks,
Venkat

By: Anonymous

Anonymous — Tue, 09 Feb 2010 18:37:47 +0000

Hi,
My website is rewrited without using file extensions like:

http://www.domain.com/dir1/
http://www.domain.com/dir2/
http://www.domain.com/dir3/dir4/

Internally pages are .aspx, but gzip compression doesn't work.

It works if pages are accessed directly:

http://www.domain.com/page.aspx

Do you know how can I configure IIS?

Thank's!

By: chang

chang — Wed, 11 Nov 2009 09:21:54 +0000

i like ur website. thanks for this comment posting...
Add

By: Gabe Sumner

Gabe Sumner — Sat, 11 Jul 2009 04:57:33 +0000

Very helpful article! Thanks so much for taking the time to write this.

By: Anonymous

Anonymous — Fri, 13 Mar 2009 16:07:00 +0000

Can it compress swf files. I have a flash site and i wants to know , if this can compress .flv and .swf files.

By: Nishaanth

Nishaanth — Fri, 06 Mar 2009 10:35:00 +0000

Nice article. You could have added the browsers compatibility list for gzip too..

By: Spud

Spud — Thu, 05 Mar 2009 09:16:00 +0000

gZip is something we looked into but shied away from as IE6 isn't fully gZip compliant. What do you do about the large % of unfortunate IE6 clients?

Otherwise, great article :)

By: Raj

Raj — Wed, 04 Mar 2009 14:43:00 +0000

Trackback from dotnetjunkies
http://www.dotnetjunkies.ddj.com/Article/16267D49-4C6E-4063-AB12-853761D31E66.dcik

What Ashish has forgotten to mention is that the two Matabase Properties (HcOnDemandCompLevel and HcDynamicCompressionLevel) can be tweakd to set the level of compression you desire. Higher compression levels generally result in small compressed files but with higher CPU and memory usage. So, one has a beefy server then by all means bump these values up, else you can experiment a little bit to get the optimum balance.

The Valid compression levels for both properties range from 1 to 10. (10 being max compression and 1 being lowest)

HcOnDemandCompLevel Metabase Property (IIS 6.0)
http://www.microsoft.com/technet/prodtechnol/WindowsServer2003/Library/IIS/c63788cc-70b4-4a44-a9a3-329fa8fb3afb.mspx?mfr=true

HcDynamicCompressionLevel Metabase Property (IIS 6.0)
http://www.microsoft.com/technet/prodtechnol/WindowsServer2003/Library/IIS/0d785bb2-8b9b-46db-96a5-a8343970324b.mspx?mfr=true

Also, that these compression settings apply at IIS level and will be applied to all the websites hosted under it.

Hope this helps.

By: Sashi

Sashi — Tue, 03 Mar 2009 10:37:00 +0000

I have used this in one of my projects earlier.
There are a few things to note before making a decision on using this technique.

1) Compression works fine for dynamic pages only when the content is not frequently changing.

2) The first call takes more time to fetch all the pages and compress. Subsequent requests can serve from the cache and will be faster.

3) This is efficient only for pages with lot of content and/or images. (Big page size). If used for smaller pages, the overhead in compression/decompression of the files will over shadow the quick download times.

Hope this helps.

By: admin

admin — Tue, 03 Mar 2009 10:21:00 +0000

@Anonymous
"Interesting, this might come in useful. But, to play devil's advocate, did you notice that the loading times were all longer for the compressed pages above?"

Yes you are correct in saying that,but the thing is that these images are for the first time load after compression been applied so they are taking time while getting compressed on the server.For the next call the time figures will also reduce as the IIS will server the already compressed content in case of static pages and also if dynamic pages have not changed then the same reason applies to the dynamic pages also.
Also i have already mentioned that when it is advisable to use the dynamic compression and when it is not advisable to implement this dynamic compression scheme.

@Giamm
"maybe timespan gain compressing response could be almost equal to time spent for zipping(server) an unzipping (client) files"
This can be the case in some situations but not in all so its at your own sweet will,test and match the requirement of your application then implement it.