Re: CPU waiting for I/O in Exadata Database Node
From: Stefan Koehler <contact_at_soocs.de>
Date: Wed, 23 May 2018 12:35:05 +0200 (CEST)
Message-ID: <831506600.488443.1527071706493_at_ox.hosteurope.de>
Date: Wed, 23 May 2018 12:35:05 +0200 (CEST)
Message-ID: <831506600.488443.1527071706493_at_ox.hosteurope.de>
Hello Cheng,
please be also aware that iowait might not represent what you think.
- https://support.hpe.com/hpsc/doc/public/display?docId=c02783994
- http://veithen.github.io/2013/11/18/iowait-linux.html
Best Regards
Stefan Koehler
Independent Oracle performance consultant and researcher
Website: http://www.soocs.de
Twitter: _at_OracleSK
> Ls Cheng <exriscer_at_gmail.com> hat am 22. Mai 2018 um 19:28 geschrieben:
>
> Hi
>
> I am observing quite high CPU waiting for I/O in Exadata Database Nodes (vmstat output). but from iostat there no waits at all (which is obvious since heavy I/O is done through infiniband).
>
> Anyone know what can be the CPU waiting for?
>
> Thanks
-- http://www.freelists.org/webpage/oracle-lReceived on Wed May 23 2018 - 12:35:05 CEST