Re: RAC internals - GLOBAL ENQUEUE SERVICES DEADLOCK DETECTED

"Dusan Bolek" <spambin_at_seznam.cz> wrote in message news:1131018603.285444.191120_at_f14g2000cwb.googlegroups.com...
> Thank you, that looks like something. I will try to catch a deadlock
> message in the alert log as quickly as possible, then find user
> responsible (via pid) and from V$SQL the statement that could be
> causing this trouble. It is not 100% reliable way, but could be
> usefule.
>
> Dusan
>

If the deadlock is on mode 5 enqueues at both ends, it is most likely to be the foreign key locking issue, possibly with a referential integrity constraint declared as 'on delete cascade' but not covered by a suitable index.

Look of foreign keys without indexes, and then look for code that deletes the parent, or updates the columns of the indexes protecting the parent key.

-- 
Regards

Jonathan Lewis

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