Re: (CKPT REQ) ?????

W. H. SMITH wrote: > > Barry Lemrow wrote: > > > > I have been experiencing problems where the database locks up. The onstat > > command banner contains this: > > > > INFORMIX-OnLine Version 7.21.UD3 -- On-Line (CKPT REQ) -- Up 6 days > > 05:13:28 -- 175552 Kbytes > > Blocked:CKPT > > > > This is a test/crash and burn environment with logging set to /dev/null. > > > > Can anyone explain what this means and why am I getting this? > > It means that Informix has requested a checkpoint. There are a number of reasons that the checkpoint has hung. Anything from the logs have filled (you seem to have taken care of that but you might check the onstat -l output to make sure that 1) all logs but the current have been backed up and 2) that there are not transactions in the other logs if a transaction started in particular log and has not completed, that log cannot be reused and the result is the same as not having been backed up at all). Another is that there is a process that is holding a latch on some resource. You can check onstat -s for any transaction oriented latches also look for any hung onlog processes or left over onlog sessions in the database from onlog processes that have been killed (known bug). There are others such as any session which was SELECTing from VERY busy sysmaster tables (like the sqexplain and profile tables) these selects may never end on a busy server (like a dog chasing its tail) and someone may have killed the front end that was running them but the sessions are still going. Worst case: onmode -ky and oninit Art S. Kagel