Hi, thank you Vlad for clarify I have created ticket http://tracker.firebirdsql.org/browse/CORE-5577
regards, Karol Bieniaszewski From: hv...@users.sourceforge.net [firebird-support] Sent: Thursday, July 6, 2017 12:05 AM To: firebird-support@yahoogroups.com Subject: Re: [firebird-support] Re: Detecting disk operations > 3. Page is read/write from temp object bigger then memory buffer e.g big > global temporary table, others? >> GTT's data go thru the common page cache as all other database operations. What happen when GTT will be bigger then whole mem cache? It will go to disk? If yes, how to catch such situation? Temporary files, used for GTT, is created with FILE_ATTRIBUTE_TEMPORARY attribute (on Windows), thus OS could cache its contents more aggressively than for non-temp files. Firebird doesn't control when OS decides to write data to disk. Also, Firebird doesn't flush temp files buffers to disk on commit and ignores database FW setting for these files. Is there some other situation where some “buffer” go to disk? Firebird uses temporary files for sorting and for the part of undo-log. Amount of temporary data maintained in memory (before is will go to the disk file) is controlled by the TempCacheLimit setting. Also, note, that OS could additionally cache temporary files data in memory. When OS physically writes this data to disk is out of Firebird control. P.S. Should i create ticket with feature request about collection of this stats? Yes, please. Regards, Vlad --- Ta wiadomość została sprawdzona na obecność wirusów przez oprogramowanie antywirusowe Avast. https://www.avast.com/antivirus
