Thread:Project:Support desk/Problems following upgrade to 1.22

I am currently using:


 * MediaWiki 1.22.3
 * PHP 5.3.6
 * MySQL 5.1.56

I also have APC installed.

I was previously using 1.21 without any problems. However, since upgrading to 1.22 I found that browsing to Special:SpecialPages generally fails. Looking in the Apache error log it reports "zend_mm_heap corrupted" (although sometimes there are other errors). Having done some research I disabled the Zend memory manager by adding USE_ZEND_ALLOC=0 to the environment. That fixed the problem in that Special:SpecialPages works consistently. However, after half an hour or so my server becomes almost completely non-responsive. It still responds to pings but not to HTML, SSH, FTP, etc. I have to reboot the server. Following this the Apache error log shows a number of "unable to fork" errors at around the time the server stopped responding. I have therefore re-enabled the Zend memory manager so that the server keeps working.

Any ideas as to what is going on here and how to fix it?