The cache is disabled.

[JayhawksRock]

yes, i have created, In fact it works with FF 10 but not with FF11.

I don't think it can be shared.. try creating a different cache folder for each FF version. I have seperate caches for Firefox 10, 11, 12, 13. 14 and UX

[Onej]

It`s bug, and "clear history after ff is closed" cause problems with cache at least for me. When I disable this, folder with cache on ramdisk works flawles, when I turn "history clean after closing" on, FF not even try to cache anything to ramdisk.

[kronckew]

Yes, I want to have cache on ramdisk, before ff11 update everything worked fine, I even clean install again and for few minutes it worked but stopped sudenly without notice. If I install FF 10 or 9 everything is ok.

? why, when ff already has the inbuilt memory cache do you want to disable it then redirect the disk cache to an emulator that needs to re-process the data to fool the memory into thinking it's a disk. this extra layer is bound to use more resources and slow it down. see a very similar discussion HERE

p.s. - using both memory & disk cache in my v.11 & the 14.0a1 nightly. works fine. setting the disk cache parent directory to my usb3 drive (e:\cache_64 for 64 bit ff, e:\cache_32 for 32 bit) not only works, but created the folder 1st time i ran ff. the sub-folder setup is a bit odd in the latest versions with 16 hex numbered subfolders.

[James]

It`s bug, and "clear history after ff is closed" cause problems with cache at least for me. When I disable this, folder with cache on ramdisk works flawles, when I turn "history clean after closing" on, FF not even try to cache anything to ramdisk.

If you chose to have Clear private data at shutdown then the disk cache is disabled. Not a bug but a feature in Firefox 11.0 to help with faster shutdown.

[Diamanti]

It`s bug, and "clear history after ff is closed" cause problems with cache at least for me. When I disable this, folder with cache on ramdisk works flawles, when I turn "history clean after closing" on, FF not even try to cache anything to ramdisk.

If you chose to have Clear private data at shutdown then the disk cache is disabled. Not a bug but a feature in Firefox 11.0 to help with faster shutdown.

Also to me disable "clear history after ff is closed" solve but why "Not a bug but a feature"? I will use cache and clear at shutdown!!!

[perert]

The problems that were fixed by changing "clear cache on shutdown" into "use ram cache instead and clear it on shutdown" are pretty clear. The reason you clear the cache on shutdown is for privacy. But say the browser crashes - that doesn't go through the normal process so the cache is not cleared, so your privacy is compromised.
The other problem it improved was slow shutdown and the "firefox is already running" error when restarting firefox - clearing a large disk cache can take more than 3 minutes, even more than 5 minutes if a bad antivirus program is getting in the way, and your profile (not only the cache) can be corrupted if you shut down the computer during that time. Also during that time you can't restart firefox which is a very common complaint and confusion to users.