484182 - images with certain file names not being cached

Status: RESOLVED DUPLICATE of bug 290032

(Firefox :: General, defect)

Description

[jedierikb]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US) AppleWebKit/525.19 (KHTML, like Gecko) Chrome/1.0.154.48 Safari/525.19
Build Identifier: 3.0.7, 3.1b3, 3.6a1pre (Minefield)

Some png image files are not being cached in the browser (monitoring with about:cache).  Changing the same file's name allows the images to be properly cached.

The headers on the image files are set so that the image is cache-able.

Reproducible: Always

Steps to Reproduce:
   1. Clear your cache.
   2. Re-load this page.
   3. Click for the first page of images.
          * Each 'page' of images consists of 10 png files. 
   4. Click again and again to load the next few pages. Monitor your about:cache.
          * Note that the initial page of images raises the cache by 20. That's expected.
          * The next page of images, page 5, only adds 4 items to the cache. That's not expected.
          * But page 8 adds 20 new files to the cache. What is it about page 8's images?
          * When we cycle arond to page 1 (remember, we start on page 4), nothing new is added to the cache! Same for pages 2 and 3. 
   5. Finally, we have made a second page (http://mediamods.com/test/ffox_cache2.html) where the file names have been changed to 0.png through 199.png. Everything is loaded into the cache with every new page. 
Actual Results:  
Not all of the files are cached when first loaded prompting firefox to re-request them from the server sometimes.  Causes slow performance.

Expected Results:  
Once downloaded, these images should have been cached.

Please refer to our second page (http://mediamods.com/test/ffox_cache2.html) for  expected behavior.

Thanks.

Comment 1

[jedierikb]

can reproduce on vista and osx.

Comment 2

[John P Baker]

Going from the description - rather than actually debugging - my first
inclination is towards bug 290032

Comment 3

[Joe Drew (not getting mail)]

Yes, if you're going by about:cache, it's almost certainly bug 290032.