On Wed, 2008-02-06 at 14:42 -0500, Tom Lane wrote: > Simon Riggs <[EMAIL PROTECTED]> writes: > > There were only 2 lock delays for FirstLockMgrLock in SHARED mode, so it > > seems believable that there were 0 lock delays in EXCLUSIVE mode. > > Not really, considering the extremely limited use of LW_SHARED in lock.c > (GetLockConflicts is used only by CREATE INDEX CONCURRENTLY, and > GetLockStatusData only by the pg_locks view). For the type of benchmark > that I gather this is, there should be *zero* LW_SHARED acquisitions at > all. And even if there are some, they could only be blocking against > the (undoubtedly much more frequent) LW_EXCLUSIVE acquisitions; it's not > very credible that there is zero contention among the LW_EXCLUSIVE locks > yet a few shared acquirers manage to get burnt.
...but the total wait time on those lock waits was 24 microseconds. I hardly call that burnt. -- Simon Riggs 2ndQuadrant http://www.2ndQuadrant.com ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster
