TEMP-TABLE Performance Tuning & Other Important Stuff Dan Foreman Progress BravePoint [email protected] Introduction- Dan Foreman Progress user since 1984 This year is my 30 year anniversary with Progress Guest Speaker at dozens of Progress Conferences 1990 until Today Dan Foreman Publications Progress Performance Tuning Guide Progress Database Admin Guide Progress System Tables Guide All updated through V11.3 Hope to have them in ePub and/or Kindle format in the next few months Who Are You? Progress V6, V7, V8, V9, V10, V11 Miscellaneous Mobile phones on silent or vibrate please TT = Temp Table V11 = OE11 To Do for Next Time Does monitoring EMPTY TEMP-TABLE “lie” about the number of records deleted? Example showing dynamic temp-tables Program to show all fields for the various “pseudo VSTs” Why does tt-data1/3.p not show the dynamic TTs? What are the mystery tables (count 2, peak 9) ???? Benchmark the overhead of turning on the TT monitors Before TT there were WORK-FILEs 100% Memory resident No indexes Record access is sequential FIND FIRST > FIND LAST > FIND FIRST Increasing the size of a record can be very expensive Can potentially crash a system with three 4GL statements……. Temp-Table Basics Similar to DB Tables CRUD (Create, Read, Update, Delete) Changes are not logged to the Before Image or After Image files Subject to LBI activity unless NOUNDO is used Type 2 Storage “Areas” No record locking No latching (in DB shared memory) TEMP-TABLE Basics TT data is written to a Client temporary file with a DBI prefix DBI file is similar to a “real” DB but with no AI, BI, LG, LK files Location of Client Temp Files can be set with –T parameter Temp Files are hidden on Win & Unix Unix/Linux: Windows: -t DIR /ah Emptying a TEMP-TABLE EMPTY TEMP-TABLE tablename Much faster than a Loop NO-UNDO NO-UNDO on the TEMP-TABLE Definition If NO-UNDO isn’t used, changes to TT inside of a transaction are logged to a Client Temp file with lbi prefix TT Startup Options -tmpbsize – the block size used for the TT “database” Client Startup Parameter The default has changed more than once so we recommend setting it explicitly -tmpbsize 8 recommended -Bt – memory buffers for Temp-Tables Client Startup Parameter Memory = (-Bt * -tmpbsize) * (# of Clients) Pre-V11 TT Monitoring Options None – at least nothing that’s built in Monitoring the size of the DBI file is about the only useful metric available V11 Delayed TT Instantiation The app doesn't incur the overhead of instantiating a TT until it's actually referenced The pre-V11 model instantiates all TT's when a new program is run, regardless of whether they are referenced or not Use -nottdelay to revert to the old functionality Temp Table Logging “The OpenEdge Logging Infrastructure has been enhanced so that application developers can trace the creation and deletion of temp-tables in their applications. This logging capability strengthens the ability to troubleshoot applications that utilize temp-tables and ProDataSets as their primary data structures.” VSTs for Temp Tables “This ABL enhancement allows clients to gather information about the temp-tables used by the application via Virtual System Tables. These tables give the application access to database activity and status information, enabling an application to understand, debug, and tune the use of temp-tables within their application at runtime.” Progress.Database.TempTableInfo Class “Provides information about a temp-table and its indexes and provides static properties and methods for retrieving and archiving temp-table information for an ABL session” TempTableInfo Properties ArchiveIndexStatistics ArchiveTableStatistics TempTableCount TempTablePeak TempTableInfo Methods GetIndexInfoByID() GetIndexStatHistoryHandle( ) GetTableInfoByID( ) GetTableStatHistoryHandle( ) GetTableInfoByPosition( ) GetVSTHandle( ) Starter Code USING Progress.Database.*. Progress.Database.TempTableInfo:ArchiveTableStatistics = YES. Progress.Database.TempTableInfo:ArchiveIndexStatistics = YES. Instant Error Cannot set Progress.Database.TempTableInfo:ArchiveTableStatistics (15247) So you lookup Message# 15247: “Update to the property or field is not allowed. This can happen if the given object only provides read-only access to the property based on its state.” What ???? V11 Client Startup Parameters -ttbasetable -tttablerangesize Default is 0; no statistics are recorded Default for the DB –tablerangesize is 50 V11 Client Startup Parameters -ttbaseindex -ttindexrangesize Default is 0; no statistics are recorded Default for the DB –indexrangesize is 50 Try Again Using this .pf file -ttbaseindex -ttindexrangesize -ttbasetable -tttablerangesize 1 100 1 100 Progress.Database.VSTTableId Class “Provides static properties that identity the VST for returning specific temptable information for an ABL session” VSTTableId Properties ActBufferId ActIOTypeId ActSpaceId BuffStatusId IndexStatId TableStatId UserIndexStatId ActIndexId ActOtherId ActSummaryId DbStatusId MstrBlkId TransId UserTableStatId ActIOFileId ActRecordId BlockId FileListId StatBaseId UserIOId Demonstration basic.p tt2.p tt-data1.p Questions? Questions? Conference Evaluations Thank You! Contact: Dan Foreman [email protected] +1 541 908 3437 (but not right now please)
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