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deleting cache deletes the cache map files as well, from that point on, Firefox doesn't cache anymore, restart of the browser is needed. Is this intentional by any chance? Using Windows Server 2003.

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  • Last reply by quinyu

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I guess it's already pretty much described in the question. If one erases everything but the _CACHE* files by hand, the cache gets corrupted (websites don't load properly except when using Ctrl-Shift-R.) Since I think users don't wish to restart their Firefox every time they erase the cache by hand (for some of us, this is done as often as every five minutes,) I guess some sort of a fix should be issued so that Firefox doesn't kill its own cache map/index files.

I guess it's already pretty much described in the question. If one erases everything but the _CACHE* files by hand, the cache gets corrupted (websites don't load properly except when using Ctrl-Shift-R.) Since I think users don't wish to restart their Firefox every time they erase the cache by hand (for some of us, this is done as often as every five minutes,) I guess some sort of a fix should be issued so that Firefox doesn't kill its own cache map/index files.

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Not a good idea to delete Firefox files while Firefox is running.
https://support.mozilla.com/en-US/kb/Clear%20Recent%20History

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Then Firefox should warn you about this fact. The cache emptying is provided as its own function, found at: Tools/Options.../Advanced tab/Network, then click "Clear Now." There (I fail to see how I could click the button in question if Firefox was NOT running...) I wouldn't make an issue of it if it were just my fooling around, but in this case, Firefox kills its own files that would be required for better functionality.

Hope this clarifies.

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There's a big difference between clearing the cache thru Options and deleting cache files thru the Windows Explorer file interface while Firefox is running. When you clear the cache in Firefox, the places.sqlite-journal file "knows" the history has been deleted and doesn't expect to find something it knows is gone.

places.sqlite-journal is like a "temporary cache" of the cache, so Firefox doesn't have to continuously be writing to the cache. Firefox updates the actual cache on a timed or load basis, not in real-time.

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I'm sure you know a lot of your stuff. I'm also reasonably certain that I know mine as well. I know where Firefox puts its cached files (written out to the hard drive in real time, surprisingly.) In my case, it's in "C:\Profiles\<username>\Local Settings\Application Data\Mozilla Firefox\Profiles\<profile ID>\Cache." After a "Clear now," then restart, it starts putting the newly acquired (cacheable) files from the sites I tested. Without a restart, it stops putting them there anymore after "Clear now" is clicked. So you state that the behaviour of Firefox before clicking "Clear now" is not caching at all, but something else, and Firefox keeps on caching even after clicking that godforsaken button, just keeps it much more well hidden or in the memory, for some reason? I don't use Windows Explorer though, it's a bother. Your familiar blue-bg two-panel friendly app does it :P

I do not wish to challenge your expertise, but are you certain it works the way you described?

I propose an experiment. Do a "Clear now," observing (in Windows Explorer or alternative) the Cache folder's content. Then go to http://media.viz.com/flash/omv/index.php?x=rin/rin_80. This is a comic page, with a shockwave flash container for each of the comic pages. Observe the Cache folder closely. Nothing's written out.

Upon closing then restarting Firefox, and visiting the same page, the Cache suddenly (immediately upon visiting the page) starts saving the data.

Your explanation ("... updates the actual cache on a timed or load basis, not in real time.") is thus not true; Firefox wouldn't need to behave differently in the two circumstances, would it? While at it: are you actually part of the developer team or somehow associated with them, at all?

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No, I am not associated with Mozilla in any manner. I am a user like almost every other "support helper" here.

Firefox doesn't cache Windows Media files, they are in the Windows Temp files. Flash has its' own cache.
http://www.simplehelp.net/2010/09/16/how-to-delete-your-flash-cache/

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Look, don't try to get me confused. I was not talking about Windows Media files. In this case it is irrelevant whatever Flash would store in its own cache, since the basic displaying Flash script actually forces a reload on anything, and stores it in the Mozilla Cache folder. Try the experiment first, then share your opinion/explanation if you still have one.

Had I wanted to delete my Flash cache (which is not used in this case,) I surely wouldn't ask it here, would I?

And (mind you, this is just again techie thing) regardless of who stores what wherever, Firefox needs the following four files there: _CACHE_001_, _CACHE_002_, _CACHE_003_, _CACHE_MAP_. They are the reference files for the content of the cache, they exist and must exist for any file retrieval attempt from the cache, even if no files are cached at all. Previous versions of Firefox left these four files alone. The current (above-named) version does not.

This is what I wish to receive help with, (either the developers patching it since they see it as a bug, or find a way to force Firefox to behave properly, i. e. not destroying its own files.)

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Look & mind you - I don't like your attitude, and as a volunteer I won't continue to help you any longer in this thread.

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That is a useful info, thanks, cor-el. I have experimented with it, and found the following:

--after a fresh start, the about:cache page displays the proper information regarding the cached files, both in amount as well as in category (i. e. disk cache and memory cache.) It changes as new pages are browsed, just as expected of it. So far so good.

--after clicking the "Clear now" button, the about:cache page does not load, and if a previously loaded about:cache page existed (in a tab or in a separate window,) it does not refresh. This is true even if you open another Firefox window and try to get the page from there.

--On closing Firefox altogether then starting it anew, the about:cache page exists again, and behaves normally, until you press the "Clear now" button. After that, it yet again fails to load and refresh.

This, putting it together, yet again seems to suggest to me that Firefox indeed ruins its own caching altogether, if that button is pressed -- precisely what I was trying to get through to the-edmeister as well, however he did not seem to get it, perhaps it's self-importance issues with "I'm knowledgeable and whatever I say must be right, I don't need to examine, and I'll dump a good amount of techspeak on you, just for a good measure, so it boosts my "answered questions" stats all the same." or something. I still maintain this is a bug, though, particularly if even the about:cache page stops working.

Thanks, and could something be done about this?

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If I clear the browser cache then that leaves me with the _CACHE_MAP_ (276 bit) and _CACHE_00X_ files (4 KiB) in the cache folder. If that doesn't happen for you then you may have some security software that is keeping an eye (or file handle) on those files and prevent Firefox from handling them correctly.

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I am using Eset SS4 as my only security software that actually accesses anything on the filesystem level... it doesn't have anything integrated into Firefox really, from what I know (and shows nothing of the kind in my System Details either...)

Utilizing the general system-digger utilities (Process Explorer and Unlocker,) it appears the only software that has an open file handle on the files in question is Firefox. I am completely lost here. Interestingly, the files still get deleted after setting their attributes to "read-only," "hidden" and "system." (To be precise, not deleted, but moved to another directory called Cache.Trash. Firefox finds his ways :] This directory exists until the shutdown of Firefox. There is no locking handle on the files after they have been moved.)

However, after clearing, nothing gets updated in the case of either of those files. That means Firefox had stopped caching. I understand this appears to be system-specific, but I understand not why it happens. I never had any problems with disappearing files otherwise, and the fact that the _CACHE_***_ files are moved together to the same place as all the other deleted stuff still makes Firefox (one way or the other) a strong suspect for me... sorry for being like this.

Question: how could I manage to figure what process/system call moves the _CACHE_***_ into the Cache.Trash as well? Do I need some special software for it to track it down? (We can have a go at it with Syser, but I'd need some more detailed instructions for this purpose.) Might it be that my hardware components are the culprit (probably the most unlikely...,) or some installation issues are at hand with my Firefox? Dang, I'm totally lost now.