Re: Does oracle db serialize concurrent read-only SELECT ?

Set timed_statistics = true, then start each session, run the test, then do a listing of v$session_event for the session. Order
by total wait time (descending), and see if this tells you where most of the time was lost. List the max-wait-time as well.

There is a bug with VxFS and concurrent
file reads (pread64()) that results in severe contention and wait times; I wonder if that might be the problem.

--
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