From: Koichi S. <koi...@gm...> - 2013-09-17 02:47:36
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I've got the issue. Yes, this is what I was concerning about and I appreciate for finding the issue and possible cause. How much you're in a hurry? I'm now in Chicago for Postgres Open and might not have a time to look into it until I finish my presentation tomorrow. Regards; --- Koichi Suzuki 2013/9/16 Nikhil Sontakke <ni...@st...> > Hi, > > One of our customers reported the following issue on the Standby: > > 1:140638715778816:2013-09-13 07:08:11.351 EDT -ERROR: GTM_TransactionInfo > already in use. Cannot assign the transaction: handle (3745). > > I investigated this and thought I had fixed this with the patch that I > have provided on the thread with $SUBJECT (Issues with GTM Standby Syncup) > > That patch reduced the number of these messages, but yet, some still found > their way into the Standby logs. > > What's happening is that GTM Standby as part of the initial syncup with > the GTM, sends gtm_standby_end_backup() after which the main GTM activates > all the threads which had been paused earlier for the syncup. > > In the time between Standby calls the above function and actually starts > listening for incoming data, some packets from the GTM are lost. Remember > this will be the case when the GTM is already very highly loaded and lots > of threads are running. > > If these packets contain commit info for those GXIDs that were added in > the initial syncup, then they are lost and as a result these slots do not > get cleaned up at the standby causing the above error messages. > > I think the best fix would be to delay and send gtm_standby_end_backup() > inside the Serverloop, JUST before the Standby is going to do the select() > call. Am trying a patch on similar lines but getting some issues, will get > back with a patch soon. > > Regards, > Nikhils > -- > StormDB - http://www.stormdb.com > The Database Cloud > > > ------------------------------------------------------------------------------ > LIMITED TIME SALE - Full Year of Microsoft Training For Just $49.99! > 1,500+ hours of tutorials including VisualStudio 2012, Windows 8, > SharePoint > 2013, SQL 2012, MVC 4, more. BEST VALUE: New Multi-Library Power Pack > includes > Mobile, Cloud, Java, and UX Design. Lowest price ever! Ends 9/20/13. > http://pubads.g.doubleclick.net/gampad/clk?id=58041151&iu=/4140/ostg.clktrk > _______________________________________________ > Postgres-xc-developers mailing list > Pos...@li... > https://lists.sourceforge.net/lists/listinfo/postgres-xc-developers > > |