Re: LMT concurrency

I've just run a slightly extreme test.
3 concurrent processes creating a
 table in an LMT with 32K uniform
extents - Each table was defined
with (initial 600MB) leading to an
initial allocation of about 19,800 extents.

Total elapsed time 2 Minutes. (And 12
seconds to drop concurrently).

There were a few seconds of lost
time on log file switches - I only had
5MB logs. A couple of seconds lost
to latches, buffer busy waits, and
enqueue waits.

The buffer busy waits were for type
10 ('unused') buffers. The few latch
sleeps were scattered across all
sorts of things, and the enqueues were
split between TX, TT, and HW.

--
Jonathan Lewis

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Ricky Sanchez wrote in message <3B3E5619.6582FD2D_at_more.net>...


>I suspect it is a buffer pin that protects the bitmaps, in the same

>manner of freelist management within a segment, but I am not sure.

>Perhaps I will figure it out.

>

>- ricky

>