RE: back-bdb deadlocks

["Kurt D. Zeilenga" <Kurt@OpenLDAP.org>]

At 06:22 PM 2002-01-17, Howard Chu wrote:
>All of a sudden the lock detector is working on my SuSE 6 system again,
>but the test takes far too long. With no transactions the test runs in
>just over a minute. With transactions it takes about 35 minutes on my
>system. I added a ldap_pvt_thread_yield() after the txn_abort() and that
>brought the runtime down to 23 minutes. Finally I got sick of it and just
>decided to serialize the whole thing. As an experiment, I obtained a BDB
>lock on the parent DN. That brings the test down to 3 minutes, 0 deadlocks.

Even that's pretty slow.  I see on my old FreeBSD devbox (2*P350)
with userland threads (one execution context).  For -008:

  1.323u 1.586s 1:18.83 3.6%      222+3232k 68+265io 148pf+0w

Have you updated glibc/pthreads, did you completely rebuild bdb?
I wonder if NGpthreads for Linux (from IBM) would help.

1/2743070       File/offset for last checkpoint LSN.
0/0     No pending checkpoint LSN.
Thu Jan 17 21:01:23 2002        Checkpoint timestamp.
80000136        Last transaction ID allocated.
20      Maximum number of active transactions possible.
0       Active transactions.
3       Maximum active transactions.
310     Number of transactions begun.
5       Number of transactions aborted.
305     Number of transactions committed.
0       Number of transactions restored.
16KB    Transaction region size (16384 bytes).
0       The number of region locks granted after waiting.
637     The number of region locks granted without waiting.

73 Last allocated locker ID.
9       Number of lock modes.
1000    Maximum number of locks possible.
1000    Maximum number of lockers possible.
1000    Maximum number of objects possible.
150846  Current locks.
150864  Maximum number of locks so far.
0       Current number of lockers.
22      Maximum number  lockers so far.
0       Current number lock objects.
16      Maximum number of lock objects so far.
178824  Number of lock requests.
178824  Number of lock releases.
0       Number of lock requests that would have waited.
699     Number of lock conflicts.
0       Number of deadlocks.
0       Number of transaction timeouts.
0       Number of lock timeouts.
352KB   Lock region size (360448 bytes).
19      The number of region locks granted after waiting.
199355  The number of region locks granted without waiting.