Subject Strange fbserver behavior after migrating from one Linux server to another
Author vladman992000
We are consolidating some Firebird 1.5 databases that have been running for many years without issue, and have moved them to a CentOS 5 64 bit server, away from their original CentOS 32 bit server. Everything appeared to be fine following migration - these are web applications so we tested them and they were operating ok.

About a day or so later, the Firebird 1.5 Super Server on the new CentOS server went into some form of tailspin. TOP reported it at 99% CPU and running over and over. Client applications stalled.

In attempting to diagnose where the problem was coming from, we restarted the clients but that made no difference. We could not regain control of the Firebird process and the only fix was a complete server reboot on the Firebird server. Following that, everything returned to normal.

This has been repeating now every 1-2 days with no sign of why. I've checked Firebird.log and there is nothing there to identify any issues. There are 5 databases (.fdb) on that server, and all are active. Any one of them could be cause of this, but I'm completely in the dark as to the root cause. I've checked with gstat and nothing appears out of the ordinary. These files were backed up to FBK files on the original server, scp'd to the new box and restored there.

I've run gfix over them with -v -f flags, sweep and mend options. Nothing appears to be an issue.

What is the best way to determine which database or query is consuming all the resource on this server? Is there anything in FB 1.5 that logs incoming connection requests so that we can at least identify what connections were active at the time of the server lockup? That might allow us to isolate this down to at least a single database, or if evidence shows that it doesn't seem to be specific to a database, we can diagnose the OS to see if there are any problems there.

Any suggestions, advice, etc. is greatly appreciated.