On Tue, May 02, 2006 at 12:06:30PM -0700, Tony Wasson wrote: > Ah thanks, it's a bug in my understanding of the thresholds. > > "With the standard freezing policy, the age column will start at one > billion for a freshly-vacuumed database." > > So essentially, 1B is normal, 2B is the max. The logic is now.. > > The script detects a wrap at 2 billion. It starts warning once one or > more databases show an age over 1.5 billion transactions. It reports > critical at 1.75B transactions. > > If anyone else understands differently, hit me with a clue bat. You should take a look at the code in -HEAD that triggers autovacuum to do a XID-wrap-prevention vacuum, as well as the code that warns that we're approaching wrap. From memory, the limit for the later is max_transactions << 3 Where max_transactions should be 4B on most platforms. I'm intending to submit a patch to clean some of that code up (put all the thresholds in one .h file rather than how they're spread through source code right now); if you drop me an email off-list I'll send you info once I do that. -- Jim C. Nasby, Sr. Engineering Consultant jnasby@xxxxxxxxxxxxx Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461
