AIO on HP-UX? Are you using Raw /ASM ? HP-UX scheduler may cause similar problems. Did you installed latest PHKL scheduler cumulative patch? Regards Andrey Nikolaev http://andreynikolaev.wordpress.com > > DB: 11.1.0.7 > HP-Unix > > > We have a database used for ETL/data loads and then the data is fed to an > oltp. We had performance issues on it yesterday and noticed that the waits > were on log file sync. The day before we did a comparable data load > without > issue. So we ran an AWR report during each period and a differential awr > report. We noticed that the day before we were handling 50% more > redo/second > during a similiar load and time of day. Nothing has changed. We looked at > other waits and nothing else seems to be standing out. From there we ran > an > oradebug hanganalyze 2 and noticed something odd. It seems that the chains > are all pointing back to the asynchronous IO. We have run 10046 trace to > look at timing events on the waits and they appear to be longer than they > should. We have referred this back to the system admins to see what they > can > tell us.I tried to google around and look on the oracle support site, but > I > do not see much about the async disc IO event. There is an oracle > background > process that strictly has this event and when I ran a 10046 trace on it, I > did not see anything that would immediately lead me to believe there are > issues. oracle support does briefly mention a bug related to ksfd > immediately after a patch, but we have not applied a patch recently. > > Has anyone seen a hang analyze like this? > > Chains most likely to have caused the hang: > [a] Chain 1 Signature: 'ksfd: async disk IO'<='log file sync' > Chain 1 Signature Hash: 0x1016ca92 > Chain 2 Signature: 'ksfd: async disk IO'<='log file sync' > Chain 2 Signature Hash: 0x1016ca92 > [c] Chain 3 Signature: 'ksfd: async disk IO'<='log file sync' > Chain 3 Signature Hash: 0x1016ca92 > > > > ------------------------------ > > End of oracle-l Digest V8 #146 > ****************************** > > > > -- //www.freelists.org/webpage/oracle-l