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CDN getting an "F" on all locations? - Printable Version

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CDN getting an "F" on all locations? - DJMorrisInc - 06-27-2010 06:07 AM

I have got MaxCDN now and at first my CDN score was a "C" for the first day, but now it is an "F" for all locations and browsers...how is this possible and what am I missing besides a screw or two? Also, I set up PHP Speedy and am running that along with w3-total cache and yet my js and css is still not compressed? Sorry to be a pain, but this is confusing stuff to the computer illiterate!


RE: CDN getting an "F" on all locations? - pmeenan - 06-27-2010 06:24 AM

Looks like some of the content is still coming directly from jupiterflhomes.com (particularly the ones that go through the thumbnail generator) as well as the requests to mls-photos.diversesolutions.com.

If you go to the checklist it will show you every request that had a problem:

FAILED - http://jupiterflhomes.com/wp-content/plugins/dsidxpress/css/client.css
FAILED - http://jupiterflhomes.com/wp-content/plugins/php_speedy_wp/cache/_cmp_cssstylesheet_f596180f6f65c84525892ea5be8ca5f9.php
FAILED - http://jupiterflhomes.com/wp-content/plugins/sexybookmarks/js/sexy-bookmarks-public.js?ver=
FAILED - http://jupiterflhomes.com/wp-content/themes/thesis_17/lib/scripts/thumb.php?src=http%3A%2F%2Fjupiterflhomes.com%2Fwp-content%2Fuploads%2F2010%2F04%2FAbacoa-Valencia-Home-For-Sale.jpg&w=175&h=125&zc=1&q=100
FAILED - http://jupiterflhomes.com/wp-content/themes/thesis_17/lib/scripts/thumb.php?src=http%3A%2F%2Fjupiterflhomes.com%2Fwp-content%2Fuploads%2F2010%2F04%2FTuscany-at-Abacoa-Homes-For-Sale.jpg&w=175&h=125&zc=1&q=100
FAILED - http://jupiterflhomes.com/wp-content/themes/thesis_17/lib/scripts/thumb.php?src=http%3A%2F%2Fjupiterflhomes.com%2Fwp-content%2Fuploads%2F2010%2F05%2FIsland-at-Abacoa-Homes-For-Sale.jpg&w=175&h=125&zc=1&q=100
FAILED - http://jupiterflhomes.com/wp-content/themes/thesis_17/lib/scripts/thumb.php?src=http%3A%2F%2Fjupiterflhomes.com%2Fwp-content%2Fuploads%2F2010%2F05%2FValencia-at-Abacoa-Homes-For-Sale.jpg&w=175&h=125&zc=1&q=100
FAILED - http://mls-photos.diversesolutions.com/266/r2917786/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r2930825/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r2988835/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3030159/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3031383/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3054686/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3068604/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3087032/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3088258/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3088285/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3089390/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3089468/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3089768/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3099892/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3105241/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3110086/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3114711/0-thumb.jpg
FAILED - http://mls-photos.diversesolutions.com/266/r3116469/0-thumb.jpg

I'm not sure what kind of control you have on the diversesolutions assets but if you can change the url at all you could reference them through your CDN account as well (just configure a new pull zone).

RE: CDN getting an "F" on all locations? - DJMorrisInc - 06-27-2010 06:28 PM

All those FAILED thumb.jpg's were coming from one widget and once I removed it my test results for IE7 were http://www.webpagetest.org/result/100627_K3E/ and IE8 http://www.webpagetest.org/result/100627_K3F/ . Doesn't quite fix the root of the problem, but it helped.

Is there a way to easily improve my text compression? Also, I am not sure why IE7 gives my js and css an "A" and IE8 gives it an "F"...that doesn't make much sense to me at all? I promise that I am going to figure all this stuff out real soon Big Grin!

RE: CDN getting an "F" on all locations? - pmeenan - 06-27-2010 11:23 PM

Looks like I need to tweak the js and css logic a bit. Right now it considers any js or css files that start before the "start render" time and recommends that they get combined. In the case of IE8 it goes through the requests fast enough that your js files (presumably at the bottom of the body but certainly somewhere outside of the head) get started before the page is rendered.

I need to tweak the logic to only consider files that finish before start render (so that they are blocking the render).

if the widget was useful, don't necessarily remove it - it's just that the performance for that widget wasn't as fast as it could be but I'd never recommend removing valuable user features for something like a CDN issue (though if you can tweak the widget to use your CDN even better).

The compress text problem looks like it is for resources coming through the CDN:

FAILED (18.5 KB, compressed = 4.8 KB - savings of 13.7 KB) - http://jupiterflhomes.jupiterfloridaho.netdna-cdn.com/wp-includes/js/jquery/ui.draggable.js?ver=1.7.3
FAILED (17.8 KB, compressed = 5.4 KB - savings of 12.4 KB) - http://jupiterflhomes.jupiterfloridaho.netdna-cdn.com/wp-includes/js/jquery/ui.resizable.js?ver=1.7.3
FAILED (12.3 KB, compressed = 4.0 KB - savings of 8.4 KB) - http://jupiterflhomes.jupiterfloridaho.netdna-cdn.com/wp-includes/js/thickbox/thickbox.js?ver=3.1-20100407
FAILED (10.7 KB, compressed = 3.6 KB - savings of 7.1 KB) - http://jupiterflhomes.jupiterfloridaho.netdna-cdn.com/wp-includes/js/jquery/ui.dialog.js?ver=1.7.3
FAILED (8.3 KB, compressed = 3.3 KB - savings of 5.0 KB) - http://jupiterflhomes.jupiterfloridaho.netdna-cdn.com/wp-includes/js/jquery/ui.core.js?ver=1.7.3

There should be a compression checkbox in your pull-zone configuration. Make sure it is checked and enabled for all of the different file types.

RE: CDN getting an "F" on all locations? - DJMorrisInc - 06-28-2010 02:31 AM

(06-27-2010 11:23 PM)pmeenan Wrote:  There should be a compression checkbox in your pull-zone configuration. Make sure it is checked and enabled for all of the different file types.

Great advice, and I went in and checked the box in MaxCDN, which I was obviously unaware of....I'll run another test, but I am sure that will be a good solution. I love this forum....I learn something new every day. Thanks!

Update Smile...I ran another test after checking the compression and fixing 6 of my social icons that FAILED being compressed to 8 bit, so I just used photoshop to make the files smaller....I finally got my test results satisfactory http://www.webpagetest.org/result/100627_KC4/ BUT of course not all is fine and dandy because my start render time and load time are now slow? I hope this is just cache or something simple Big Grin!

RE: CDN getting an "F" on all locations? - jklein - 06-29-2010 02:55 AM

Strange, your first byte time just tanked in that most recent test. I ran another test and it went back down to a normal level, so I wouldn't worry about it:


You would definitely see some improvements in render time by merging JS files and spriting some of your icons. You could easily get rid of 10+ HTTP requests on that page which would likely speed things up considerably.
It is also worth noting that the client CPU is getting pegged about halfway through your waterfall chart - that it what is causing the gap in the waterfall. This usually happens because you have a ton of JS running or a really inefficient code loop of some sort. Fixing that would be a big win - you may be able to use dynatrace to help you diagnose the problem:


Dynatrace is also having a free webinar on Wednesday to demo the new version of Dynatrace Ajax Edition. You can read about all of that here: