Am 22.02.2011 11:40, schrieb Nicola Cerchiari: > Hi to all, > First time here suggested by friends of the italian mialing list; i'm > encountering a very annoying problem of which I can find no solutions. > > The problem is that randomly during day calling any backend action hang the > browser on "waiting for response..." and the only solution left is to stop > the call, wait several minutes and then everything is back to normal until > it happens again. > For example the same action works for 2 hours and then all of a sudden > hangs. Even accessing to backend login page sometimes hangs. > I've tested the same website and core on my test machines and I never > encounter any problem. > I give you some data in other to better understand the situation: > - php 5.2.x with all libraries needed > - mysql 5.1.55 in replication master/slave (just updated) > - 2 balanced webserver apache/redhat (on a vmware virtualized farm) > - filesystem of webserver ron a shared NAS > - version of typo3 on which the problem is encountered: 4.4.6 and 4.5.0 > > The matter is that when backend works, works pretty fast, but the nall of a > sudden with apparently no reason it hangs. > > System admnistrators of the infrastructure suggested at first that there was > a "strangly" large amount of calls in TIME_WAIT state, then they suggested > maybe the mysql server is not tuned sufficiently to stand the increasing > requests (consider that this infrastructure receive >50.000 user visit a > day) and they will try a fine tuning in the next day. > > What i'm looking for is to understand if the problem is due to Typo3 (i > don't think so) or there is some problem in our infrastructure. > > Any ideas? > > > Thank you in advance, > Nicola
Possible causes: clearing cache: lots of rather slow delete queries on db -> there is a extension to use truncate table for clearing the cache. stalling locking ( there are some race conditions left in the locking code, check the bugtracker) DB-backup not excluding the cache tables: huge amount of data with table locking, so lots of db request waiting foe the lock to become released. Björn _______________________________________________ TYPO3-english mailing list TYPO3-english@lists.typo3.org http://lists.typo3.org/cgi-bin/mailman/listinfo/typo3-english