TYPO3 Core

I get the same errors on a XAMPP environment (windows 10); my installation is TYPO3 9.5.3, completely fresh installation (nothing installed except system extensions and empty default page)

for me on xampp with win 10
a workaround like

 $res = @rename($temporaryCacheEntryPathAndFilename, $cacheEntryPathAndFilename);
       if (!$res) {
           $e = copy($temporaryCacheEntryPathAndFilename, $cacheEntryPathAndFilename);
            unlink($temporaryCacheEntryPathAndFilename);

       }

see also https://github.com/doctrine/common/pull/874

Markus Dübbert wrote:

local ddev installation on windows 10

If you start the docker-desktop with administrative priviliges the error disappears.

Tymoteusz Motylewski wrote:

for me on xampp with win 10
a workaround like
[...]
worked.

see also https://github.com/doctrine/common/pull/874

I tried to modify the file /typo3/sysext/core/Classes/Cache/Backend/SimpleFileBackend.php but the error seems still present (but it is not reported on the log (?) :/ )

Additional info: on ddev environments you can get rid of the error with https://stackoverflow.com/questions/57554778/how-can-i-fix-the-caching-issue-in-typo3-and-ddev

It seems to me that the root of this is that TYPO3 uses a filesystem as if it were tmpfs (<projectroot>/var/cache) when that may well be a slow filesystem, as it is whenever it's mounted from anywhere, as with ddev. Is there a reason that TYPO3 doesn't have a configured cache directory that's actually tmpfs, for example just pointing it to /tmp ?

For ddev, it would be possible to work around this by automatically setting var/cache to be a tmpfs mount. But since the problem appears in many environments (mostly Windows it seems) it may be better to just move that cache to a more appropriate place?

Randy Fay wrote:

It seems to me that the root of this is that TYPO3 uses a filesystem as if it were tmpfs (<projectroot>/var/cache) when that may well be a slow filesystem, as it is whenever it's mounted from anywhere, as with ddev. Is there a reason that TYPO3 doesn't have a configured cache directory that's actually tmpfs, for example just pointing it to /tmp ?

For ddev, it would be possible to work around this by automatically setting var/cache to be a tmpfs mount. But since the problem appears in many environments (mostly Windows it seems) it may be better to just move that cache to a more appropriate place?

Good idea to offer a tmpfs cache! Unfortunately it looks like the cache directory can't be changed because the setter function setCacheDirectory() is never called in TYPO3 v10.
So the most simple way to do this is to mount a tmpfs filesystem on top of typo3temp/var/Cache/.

On a single-host site, the workaround using tmpfs would work. However, in a multi-host setup with a single database, the typo3temp folder should be the same on all hosts, therefore it needs to be shared using NFS, CephFS, etc.

I was adding comments here because I ran into a very similar problem. However, just decided to move my comments into a separate issue #91768.