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IBM 000-8697 Step 4: Roll Back Incomplete Transactions

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4-44 IBM Informix OnLine Database Server Administrator’s Guide

Step 4: Roll Back Incomplete Transactions

Step 4: Roll Back Incomplete Transactions

The ﬁnal step in fast recovery is to roll back all logical log records that are

associated with transactions that were not committed (or were rolled back).

This rollback procedure ensures that all databases are left in a consistent

state.

Sinceit is possible that one or more transactions have spanned several check-

points without being committed, this rollback procedure might read

backwardthrough the logical log past the most-recent checkpoint record. All

logical log ﬁles that contain records for open transactions are available to

OnLinebecause a log is not freed until all transactions contained within it are

closed.Figure 4-7 illustrates the roll-back procedure. When fast recovery is

complete, OnLine goes to quiescent or online mode.

Figure4-7

Fast recovery,

step4

Fast Recovery: Step 4

OnLine rolls back all incomplete transactions, ensuring that all databases are

left in a consistent state. Records written earlier than the checkpoint might be

rolled back.

Disk A

Logical log

Uncommittedchanges

rolled back

Contents

Main ii IBM Informix OnLine Database Server Administrators Guide Table of Contents Table of Contents Introduction Chapter 1 Installation and Initial Conguration Chapter 2 System Architecture Page Chapter 3 Operating OnLine Page Chapter 4 Data Consistency, Recovery, and Migration Page Chapter 5 How to Improve Performance Chapter 6 DB-Monitor Screens Chapter 7 Utilities Page Chapter 8 OnLine Message Log Chapter 9 Product Environment Appendix A Notices Index Introduction Introduction Page In This Introduction About This Manual Organization of This Manual Organization of This Manual Demonstration Database Demonstration Database Demonstration Database IBM Informix OnLine IBM Informix OnLine Product Overview IBM Informix OnLine and Other IBM Informix Products Documentation Conventions Documentation Conventions Typographical Conventions Icon Conventions Icon Conventions Command-Line Conventions Command-Line Conventions Elements That Can Appear on the Path You might encounter one or more of the following elements on a path. Command-Line Conventions How to Read a Command-Line Diagram Sample Code Conventions Sample Code Conventions Sample Code Conventions Additional Documentation Additional Documentation Printed Manuals Error Message Files Using the ASCII Error Message File The nderr Script The rofferr Script Documentation Notes, Release Notes, Machine Notes Using the PostScript Error Message Files Documentation Notes, Release Notes, Machine Notes Related Reading Related Reading Compliance with Industry Standards IBM Welcomes Your Comments IBM Welcomes Your Comments Installation and Initial Conguration Page Page Page Page Dene Your Starting Point Dene Your Starting Point Upgrade an Earlier Version of OnLine Compare Your Current Conguration to OnLine 5.x Create a Level-0 Archive Load the Software and Execute the install Script Initialize Shared Memory Run tbcheck Create a New Level-0 Archive Overview of OnLine Installation Steps Overview of OnLine Installation Steps Overview of OnLine Initial Conguration Tasks OnLine Conguration Files OnLine Conguration Files OnLine Conguration Files Contents of tbcong.std Page Page Page Page 1-18 IBM Informix OnLine Database Server Administrators Guide USERS species the maximum number of OnLine user processes that can Figure1-1 The Contents of tbcong.std Installation and Initial Configuration 1-19 Set Up Your Initial Conguration Set Up Your Initial Conguration Root Dbspace Conguration Guidelines ROOTNAME ROOTPATH ROOTOFFSET ROOTSIZE Mirroring Conguration Guidelines Mirroring Conguration Guidelines MIRROR MIRRORPATH Physical Log Conguration Guidelines MIRROROFFSET Physical Log Conguration Guidelines PHYSDBS PHYSFILE Logical Log Conguration Guidelines Logical Log Conguration Guidelines Logical Log Conguration Guidelines LOGFILES LOGSIZE Message File Guidelines Message File Guidelines MSGPATH CONSOLE Archive Tape Device Guidelines TAPEDEV Logical Log Tape Device Guidelines Logical Log Tape Device Guidelines LTAPEDEV LTAPEBLK Identication Parameter Guidelines LTAPESIZE Identication Parameter Guidelines SERVERNUM DBSERVERNAME Shared-Memory Parameter Guidelines RESIDENT USERS TRANSACTIONS LOCKS BUFFERS TBLSPACES CHUNKS DBSPACES PHYSBUFF LOGBUFF LOGSMAX CLEANERS SHMBASE CKPTINTVL LRUS LRU_MAX_DIRTY LRU_MIN_DIRTY LTXHWM LTXEHWM Machine- and Product-Specic Parameter Guidelines Machine- and Product-Specic Parameter Guidelines DYNSHMSZ GTRID_CMP_SZ DEADLOCK_TIMEOUT TXTIMEOUT OnLine Disk Space Allocation Allocate Raw Disk Space or Cooked Files? How Much Disk Space Do You Need? Calculate Root dbspace Size Project Total Space Requirements How Should You Apportion Disk Space? Space Allocation in a Learning Environment Space Allocation in a Production Environment Page Page How to Allocate Disk Space Cooked File Space Raw File Space Evaluate UNIX Kernel Parameters Conguration Checklist Conguration Checklist Enter Your Conguration and Initialize OnLine Enter Your Conguration and Initialize OnLine Enter Your Conguration and Initialize OnLine Setting Shared Memory Parameters Setting Shared Memory Parameters Initialize OnLine Initialize OnLine Set Your Environment Variables Set Your Environment Variables SQLEXEC TBCONFIG Modify UNIX Startup and Shutdown Scripts Startup Shutdown Create Blobspaces and Dbspaces Create Blobspaces and Dbspaces Errors During Initialization OnLine Error Message Format OnLine Error Message Format UNIX Error Message Format System Architecture Page Page Page Page Page Initialization Initialization Commands Initialization Commands Initialization Commands Shared Memory Commands Disk Space Commands What Happens During Shared-Memory Initialization Shared-Memory Initialization Procedure Step 1: Calculate Conguration Values Step 2: Create Shared Memory Step 3: Attach to Shared Memory Step 4: Initialize Shared Memory Structure Step 5: Wake Parent Process Steps 6 and 7: Initiate Fast Recovery and First Checkpoint Step 8: Drop Temporary Tables (Optional) Step 9: Document Conguration Changes Step 10: Check for Forced Residency What Happens During Disk-Space Initialization Step 1: Calculate Conguration Values Step 2: Create OnLine Shared Memory Step 3: Attach to Shared Memory Step 4: Initialize Shared-Memory Structures Step 5: Initialize Disk Space Step 6: Wake Parent tbinit Process Step 7: Initiate First Checkpoint Step 8: Change to Quiescent Mode Step 9: Set Forced Residency Step 10: Loop as Master Daemon UNIX Kernel and Semaphore-Allocation Parameters Page Page Page OnLine User Processes OnLine User Processes OnLine User Processes How User Processes Attach to Shared Memory Step 1: Obtain SERVERNUM Step 2: Calculate Shared-Memory Key Value Steps 3 and 4: Request Shared-Memory Segment and Attach to SHMBASE Page Step 5: Attach Additional Segments User Processes and Critical Sections User Processes and Critical Sections OnLine User Process Status and States OnLine User Process Status and States OnLine Database Server Process OnLine Database Server Process Orphaned Database Server Processes Orphaned Database Server Processes Orphaned Database Server Processes OnLine Daemon Processes OnLine Daemon Processes tbinit Daemon tbundo Daemon tbundo Daemon tbpgcl Daemon tbpgcl Daemon Shared Memory and Process Communication Shared Memory and Process Communication Shared Memory and Process Communication Shared Memory and Buffer Locks Shared Memory and Buffer Locks Buffer Share Lock Buffer Update Lock Buffer Exclusive Lock Managing Shared-Memory Resources Page Shared-Memory Latches Test-and-Set Institutions Spin and Test Again Semaphores Forced Abort OnLine Timestamps Page Hash Tables and the Hashing Technique Shared-Memory Header Shared-Memory Header Shared-Memory Internal Tables OnLine Buffer Table OnLine Chunk Table OnLine Dbspace Table OnLine Latch Table OnLine Lock Table OnLine Page-Cleaner Table OnLine Tblspace Table Page OnLine Transaction Table OnLine User Table Shared-Memory Buffer Pool Shared-Memory Buffer Pool Shared-Memory Buffer Pool Regular Buffers Big Buffers OnLine LRU Queues OnLine LRU Queues LRU Queues and Buffer Pool Management LRU Queues and Buffer Pool Management LRU Queues and Buffer Pool Management LRU_MAX_DIRTY LRU_MIN_DIRTY How a User Process Acquires a Buffer Step 1: Identify the Data Step 2: Determine Lock-Access Level Step 3: Locate the Page in Memory Step 4: Read the Page in from Disk Steps 5-7: Lock Buffer, Release Lock, and Wake Waiting Processes Physical Log Buffer Double Buffering Causes of Flushing Flushing a Full Buffer Logical Log Buffer Triple Buffering Page Buffer Contents Causes of Flushing Flushing a Full Buffer OnLine Checkpoints OnLine Checkpoints Main Events During a Checkpoint Initiating a Checkpoint OnLine Checkpoints Fast Recovery Archive Checkpoints What Happens During a Checkpoint What Happens During a Checkpoint When the Daemons Flush the Buffer Pool When the Daemons Flush the Buffer Pool How OnLine Synchronizes Buffer Flushing How OnLine Synchronizes Buffer Flushing Write Types Describe Flushing Activity Sorted Write Idle Write Foreground Write LRU Write Chunk Write Big-Buffer Write Writing Data to a Blobspace Page Page Disk Data Structures Disk Data Structures OnLine Disk Space Terms and Denitions Chunk Page Page Blobpage Dbspace and Blobspace Database Tblspace Extent Logical Log Structure of the Root Dbspace Structure of the Root Dbspace Structure of the Root Dbspace Structure of a Regular Dbspace Structure of a Regular Dbspace Structure of an Additional Dbspace Chunk Structure of an Additional Dbspace Chunk Structure of a Blobspace Structure of a Blobspace Structure of a Blobspace or Dbspace Mirror Chunk Structure of a Blobspace or Dbspace Mirror Chunk OnLine Limits for Chunks OnLine Limits for Chunks OnLine Limits for Chunks Reserved Pages Page PAGE_PZERO PAGE_CONFIG PAGE_CKPT The following elds display for each OnLine logical log le. PAGE_DBSP PAGE_PCHUNK PAGE_MCHUNK PAGE_ARCH Chunk Free-List Page Chunk Free-List Page tblspace Tblspace tblspace Tblspace Entries Tblspace Number tblspace Tblspace Size Database Tblspace tblspace Tblspace Bit-Map Page Database Tblspace Create a Database: What Happens on Disk Create a Database: What Happens on Disk Create a Database: What Happens on Disk Allocate Disc Space Track Systems Catalogs OnLine Limits for Databases OnLine Limits for Databases Create a Table: What Happens on Disk Create a Table: What Happens on Disk Allocate Disc Space Add Entry to tblspace Tblspace Add Entry to System Catalog Tables Create a Table: What Happens on Disk Create a Temporary Table: What Happens on Disk Create a Temporary Table: What Happens on Disk Placement Tracking Cleanup Structure of an Extent Extent Size Page Types Page Next Extent Allocation Page Page Structure of a Dbspace Page Page Header Timestamp Slot Table Page Data Row Format and Rowid Data Row Format and Rowid Data Row Format and Rowid Data Pages and Data Row Storage Single-Page Storage Multipage Storage Page Storage of Modied Rows Page Page Page Page Compression Structure of an Index Page The Root Node Page Page Leaf Node Pages Page Index Key Entries Page Page Page Page Structure of a Dbspace Bit-Map Page Structure of a Dbspace Bit-Map Page 2-Bit Bit-Mapped Pages Structure of a Dbspace Bit-Map Page 4-Bit Bit-Mapped Pages Blob Storage and the Blob Descriptor Blob Storage and the Blob Descriptor Structure of a Dbspace Blob Page Structure of a Dbspace Blob Page Structure of a Dbspace Blob Page Blobspace Page Types Blobspace Page Types Blobspace Free-Map Page Blobspace Bit-Map Page Blobpage Structure of a Blobspace Blobpage Page Page Physical Log Page Logical Log Files Logical Log Files Fast Recovery and Data Restore File Rotation File Rotation File Contents File Contents Number and Size Number and Size Blobspace Logging Long Transactions Page Page Page Operating OnLine Page Page Page Page Changing Modes Changing Modes Types of OnLine Modes Page From Ofine to Quiescent From Ofine to Quiescent From Ofine to Online From Quiescent to Online From Quiescent to Online Gracefully from Online to Quiescent Gracefully from Online to Quiescent Immediately from Online to Quiescent Immediately from Online to Quiescent From Any Mode Immediately to Ofine From Any Mode Immediately to Ofine Logical Log Administration Logical Log Administration Examine Your Logical Log Conguration Your Conguration File Logical Log File Backups Freeing the Logical Log Files Verify the Size and Number of Files Conguration Parameters LTAPEBLK and LTAPESIZE Location of Logical Log Files Change Pathname of Logical Log Tape Device Preliminary Consideration Page Change Block Size of Logical Log Tape Device Change Block Size of Logical Log Tape Device Change Tape Size of Logical Log Tape Device Change Tape Size of Logical Log Tape Device Change Maximum Number of Logical Log Files Change Maximum Number of Logical Log Files Change Size of Logical Log Files Change Size of Logical Log Files Change Size of Logical Log Files Logical Log File Status Logical Log File Status Logical Log File ID Numbers Logical Log File ID Numbers Add a Logical Log File Add a Logical Log File Add a Logical Log File Drop a Logical Log File Drop a Logical Log File Move a Logical Log File to Another Dbspace Move a Logical Log File to Another Dbspace Move a Logical Log File to Another Dbspace Change the Logging Status of a Database Adding Logging to a Database Ending or Modifying Logging from DB-Monitor Back Up a Logical Log File ANSI Compliance Back Up a Logical Log File Start Continuous Logical Log Backup Start Continuous Logical Log Backup End Continuous Logical Log Backup End Continuous Logical Log Backup Switch to the Next Logical Log File Switch to the Next Logical Log File Free a Logical Log File Free a Logical Log File Free a Logical Log File Status A Status U Status U-B Status U-C Status U-B-L If the Logical Log Backup Cannot Complete Archive Administration Archive Administration Archive Types Archive Types Level-0 Archive Archive Types Level-1 Archive Level-2 Archive Incremental Archive Strategy How Long Will an Archive Take? How Long Will an Archive Take? Plan the Archive Schedule Minimize Restore Time Minimize Archive Time Online Archives Single Tape Drive Examine Your Archive Conguration Operator Availability Examine Your Archive Conguration Your Conguration File Examine Your Archive Conguration The Archives TAPEDEV Conguration Parameter TAPEBLK and TAPESIZE Change Pathname of Archive Tape Device Page Page Change Block Size of Archive Tape Device Change Block Size of Archive Tape Device Change Tape Size of Archive Tape Device Change Tape Size of Archive Tape Device Create an Archive, Any Type Create an Archive, Any Type Create an Archive, Any Type If the Logical Log Files Fill During an Archive If the Logical Log Files Fill During an Archive Two Tape Drives If an Archive Terminates Prematurely One Tape Drive If an Archive Terminates Prematurely Monitor OnLine Activity Monitor OnLine Activity Monitor Archive History Monitor Archive History Monitor Blobs in a Blobspace Monitor Blobs in a Blobspace Monitor Blobs in a Blobspace Monitor Blobs in a Dbspace Monitor Blobs in a Dbspace Monitor Buffers Monitor Buffers tbstat -b tbstat -X Monitor Buffers tbstat -B tbstat -p Monitor Buffer-Pool Activity Monitor Buffer-Pool Activity tbstat -F Monitor Checkpoints tbstat -R tbstat -D Monitor Checkpoints Monitor Chunks Page Page Monitor Conguration Information Monitor Conguration Information Monitor Databases Monitor Databases Monitor Dbspaces Monitor Dbspaces Monitor Dbspaces Monitor Disk Pages Monitor Disk Pages Monitor Extents Monitor Extents Monitor Index Information Monitor Index Information Monitor Logging Activity Monitor Logging Activity Monitor Logging Activity Monitor the Message Log Monitor the Message Log Monitor OnLine Prole Monitor OnLine Prole Monitor Shared Memory and Latches Monitor Shared Memory and Latches Monitor Tblspaces Monitor Tblspaces Monitor Users and Transactions Monitor Users and Transactions Modify OnLine Conguration Modify OnLine Conguration Create a Blobspace Page Page Drop a Blobspace Drop a Blobspace Change the Number of Buffers in the Pool Change the Number of Buffers in the Pool Change the Size of Either Log Buffer Change the Size of Either Log Buffer Add a Chunk Page Change the Maximum Number of Chunks Change the Maximum Number of Chunks Create a Dbspace Create a Dbspace Create a Dbspace Drop a Dbspace Drop a Dbspace Enforce/Turn Off Residency for This Session Enforce/Turn Off Residency for This Session Enforce/Turn Off Residency Change the Status of a Mirrored Chunk Page Page Enable Mirroring Enable Mirroring Start/End Mirroring in a Blobspace or Dbspace Start/End Mirroring in a Blobspace or Dbspace Start Mirroring Start/End Mirroring in a Blobspace or Dbspace End Mirroring Change Physical Log Location or Size Change Physical Log Location or Size Change Physical Log Location or Size Change the Checkpoint Interval Change the Checkpoint Interval Change the Destination of Console Messages Change the Destination of Console Messages Change the Maximum Number of Dbspaces Change the Maximum Number of Dbspaces Change the Maximum Number of Locks Change the Maximum Number of Locks Change the Maximum Number of Tblspaces Change the Maximum Number of Tblspaces Change the Maximum Number of Users Change the Maximum Number of Users Change the Number of Page Cleaners Change the Number of Page Cleaners Things to Avoid Things to Avoid Data Consistency, Recovery, and Migration Page Page Page Page Consistency Checking Consistency Checking Using the tbcheck Commands Using the tbcheck Commands tbcheck -cr tbcheck -cc tbcheck -ce Using the OnLine Message Log tbcheck -cI tbcheck -cD Using the OnLine Message Log Setting Consistency-Checking Variables GCORE DUMPCORE DUMPSHMEM Recovering from Corruption DUMPDIR Recovering from Corruption Recovering from Corruption Mirroring Mirroring Beginning Beginning Processing Processing Recovery Recovery Ending OnLine Logging Overview OnLine Logging Overview Dbspace Logging Dbspace Logging Page Dbspace Logging Blobspace Logging Page Operations Logging Operations Rollback Blob Restoration What Happens During Logical Log Backup What Happens During Logical Log Backup Ready LTAPEDEV Ready LTAPEDEV Locate the Next Logical Log Copy Blobpages Place Log Header on Tape Place Log Header on Tape Write Log Records to Tape Write Log Records to Tape 1 2 3 Write Trailer Page Write Trailer Page What Happens During an Archive Read Archive History Information Read Archive History Information Mount a Tape on TAPEDEV Verify the Archive Level Verify the Archive Level Check Free Space in the Logical Log Force a Checkpoint Synchronize tbtape and tbinit Activities Purpose of Checkpoint Timestamp Synchronize tbtape and tbinit Activities Synchronize tbtape and tbinit Activities Archive Disk Pages Write Tape Header Page Archive blobpages Write Tape Header Page Archive Reserved Pages Archive Reserved Pages Determine Archive Criteria Determine Archive Criteria Archive Disk Pages That Meet Criteria Archive Disk Pages That Meet Criteria Monitor and Archive Physical Log Pages Write a Trailer Page Update the Reserved Pages Fast Recovery Fast Recovery How Does OnLine Initiate Fast Recovery? Fast Recovery and Logging Fast Recovery and Logging Step 1: Checkpoint Condition Step 1: Checkpoint Condition Step 2: Find Checkpoint Record in Logical Log Step 2: Find Checkpoint Record in Logical Log Step 3: Roll Forward Log Records Step 3: Roll Forward Log Records Step 4: Roll Back Incomplete Transactions Step 4: Roll Back Incomplete Transactions Data Restore: When Should You Do It? Data Restore: When Should You Do It? Steps That Occur During a Data Restore Steps That Occur During a Data Restore Gather All Tapes Needed for Restore Gather All Tapes Needed for Restore Verify OnLine Conguration Verify OnLine Conguration Initiate Data Restore from Ofine Mode Initiate Data Restore from Ofine Mode Mount Level-0 Archive Tape Verify Current Conguration Verify Current Conguration Prompt for Logical Log Backup Write Each Archive Page to Disk Write Each Archive Page to Disk Initialize Shared Memory Roll Forward Logical Logs OnLine Is Quiescent OnLine Is Quiescent Database and Table Migration Database and Table Migration Description of Migration Methods UNLOAD/dbschema/LOAD UNLOAD/dbschema/dbload dbexport/dbimport tbunload/tbload } Which Migration Method Is Best for You? Page Page Using UNLOAD with LOAD or dbload Using UNLOAD with LOAD or dbload Using UNLOAD with LOAD or dbload Create and Edit the Schema File First Verify Adequate Disk Space for Data Move Files Create the New Database or Tables Using dbexport and dbimport Use LOAD or dbload to Populate the Tables Using dbexport and dbimport Using tbunload and tbload Using tbunload and tbload Using tbunload and tbload tbunload tbload Migrating Data from OnLine to SE Migrating Data from OnLine to SE Migrating Data from SE to OnLine Migrating Data from SE to OnLine Page Page How to Improve Performance Page Page Disk Layout Disk Layout Optimize Blobspace Blobpage Size Optimize Blobspace Blobpage Size tbcheck -pB and tbcheck -pe Utility Commands tbcheck -pB and tbcheck -pe Utility Commands Blobpage Average Fullness Blobpage Average Fullness Apply Effective Criteria Apply Effective Criteria Eliminate User-Created Resource Bottlenecks Eliminate User-Created Resource Bottlenecks When Is Tuning Needed? When Is Tuning Needed? % Cached Fields ovtbls, ovlock, ovuser, and ovbuff Fields ovtbls, ovlock, ovuser, and ovbuff Fields Bufsize Pages/IO Fields Bufsize Pages/IO Fields Shared-Memory Buffers Shared-Memory Buffers When Is Tuning Necessary? Shared-Memory Resources Shared-Memory Resources When Is Tuning Necessary? Log Buffer Size Logging Status Page Page-Cleaner Parameters Page-Cleaner Parameters Efcient Page Cleaning Efcient Page Cleaning Page Checkpoint Frequency Checkpoint Frequency Performance Tradeoffs Page Psort Parallel-Process Sorting Package Psort Parallel-Process Sorting Package How Psort Works Tuning Psort Tuning Psort Psort and Shared Memory Psort and Shared Memory SPINCNT Conguration Parameter SPINCNT Conguration Parameter Page DB-Monitor Screens Page Page Main Menu Main Menu Status Menu Status Menu Parameters Menu Parameters Menu Dbspaces Menu Dbspaces Menu Mode Menu Mode Menu Page Archive Menu Archive Menu Logical-Logs Menu Logical-Logs Menu Page Utilities Page Page Page dbexport: Unload a Database and Schema File Page Destination Options Destination Options Destination Options Contents of the Schema File Contents of the Schema File dbimport: Create a Database dbimport: Create a Database Page Input File Location Options Input File Location Options Input File Location Options Create Options Create Options dbload: Load Data from a Command File dbload: Load Data from a Command File Page Page Command-File Syntax Check Command-File Syntax Check Starting Line Number Batch Size Batch Size Bad-Row Limits Bad-Row Limits How to Create a Command File Delimiter Form FILE Statement Delimiter Form INSERT Statement Delimiter Form Statement Examples Page Character-Position FILE Statement Page Character-Position INSERT Statement Character-Position Statement Examples Page Page dbschema: Output SQL Statements dbschema: Output SQL Statements Include Synonyms Include Synonyms Include Privileges Include Privileges Specify a Table, View, or Procedure Specify a Table, View, or Procedure tbcheck: Check, Repair, or Display tbcheck: Check, Repair, or Display tbcheck: Check, Repair, or Display 7-38 IBM Informix OnLine Database Server Administrators Guide - Option Descriptions No Options -cc Option -cd and -cD Options -ce Option -ci and -cI Options -cr Option -n Option -pB Option -pc Option -pd and -pD Options -pe Option -pk and -pK, -pl and -pL Options -pp and -pP options -pr Option -pt and -pT Options tbinit: Initialize OnLine -q Option -y Option tbinit: Initialize OnLine No Options -i Option tbload: Create a Database or Table -p Option tbload: Create a Database or Table Page Specify Tape Parameters Specify Tape Parameters Create Options Create Options tblog: Display Logical Log Contents tblog: Display Logical Log Contents Log-Record Read Filters Log-Record Read Filters -b Option Page Log-Record Display Filters Log-Record Display Filters Interpreting tblog Output Record Types Record Contents Page Page Page Page Page Page tbmode: Mode and Shared-Memory Changes tbmode: Mode and Shared-Memory Changes -y automatically responds yes to all prompts. Utilities 7-65 Change OnLine Mode Change OnLine Mode -k Option -m Option Force a Checkpoint -u Option Force a Checkpoint Change Shared-Memory Residency Change Shared-Memory Residency Switch the Logical Log File Kill an OnLine Server Process Kill an OnLine Server Process Kill an OnLine Transaction tbparams: Modify Log Conguration Parameters tbparams: Modify Log Conguration Parameters Add a Logical Log File Drop a Logical Log File Drop a Logical Log File Change Physical Log Parameters Change Physical Log Parameters tbspaces: Modify Blobspaces or Dbspaces tbspaces: Modify Blobspaces or Dbspaces Create a Blobspace or Dbspace Create a Blobspace or Dbspace Drop a Blobspace or Dbspace Drop a Blobspace or Dbspace Add a Chunk Change Chunk Status Change Chunk Status tbstat: Monitor OnLine Operation tbstat: Monitor OnLine Operation tbstat: Monitor OnLine Operation 7-80 IBM Informix OnLine Database Server Administrators Guide Page Option Descriptions Page -B Option -c Option -d Option Page -D Option -F Option -k Option -l Option Page -m Option -o Option -p Option Page Page -P Option -r Option -R option Page Page -t Option -u Option Page -X Option tbtape: Logging, Archives, and Restore -z Option tbtape: Logging, Archives, and Restore Page Request a Logical Log Backup Request a Logical Log Backup Start Continuous Backups Create an Archive Create an Archive Perform a Data Restore Change Database Logging Status Change Database Logging Status tbunload: Transfer Binary Data in Page Units tbunload: Transfer Binary Data in Page Units Page Specify Tape Parameters Specify Tape Parameters Page Page Page OnLine Message Log OnLine Message Log Alphabetized Messages Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Page Product Environment Page The OnLine Environment OnLine Features OnLine Features High Performance OnLine Features Fault Tolerance and High Availability Multimedia Support Features Beyond the Scope of OnLine Distributed Data Queries Features Beyond the Scope of OnLine Bad-Sector Mapping Blob Scanning or Compression What Is Multiple Residency? Page disk disk How Multiple Residency Works How Multiple Residency Works How to Set Up Multiple Residency Step 1: Create a New Conguration File Step 2: Edit the Conguration File for the New OnLine ROOTPATH SERVERNUM DBSERVER-NAME MSGPATH Step 3: Set Your TBCONFIG Environment Variable Step 4: Complete Tuning OnLine Conguration (Optional) Step 5: Initialize New OnLine Step 6: Ensure That Users Correctly Dene Their TBCONFIG Variables OnLine Administration with IBM Informix STAR OnLine Administration with IBM Informix STAR Sharing Data by Using IBM Informix STAR Page Updating Multiple OnLine Servers Multiserver Modication Concepts IBM Informix STAR and Two-Phase Commit Protocol Protocol Components Example Transaction Commit Example Transaction Rollback Two-Phase Commit and Automatic Recovery Coordinator Recovery Page Page Participant Recovery Page Page Independent Action and Manual Recovery Presumed-Abort Optimization Independent Action and Manual Recovery Heuristic Decisions: What and Why Page Page Page Page Page Heuristic Rollback Condition 1: Logical Log Fills to a High-Water Mark Condition 2: You Execute tbmode -z When a Heuristic Rollback Occurs Page Page Heuristic End-Transaction Page Page Two-Phase Commit Protocol Errors Two-Phase Commit Protocol Errors Two-Phase Commit and Logical Log Records BEGPREP PREPARE TABLOCKS HEURTX ENDTRANS The output fromtblog contains only the type eld, as follows: Transaction Commit Records Page Page Page Heuristic End-Transaction Records Determining Database Consistency Step 1: Determine Where a Heuristic Decision Occurred Step 2: Determine If the Networked Database Contains Inconsistent Data Steps 3 and 4: Decide If Correction Is Needed Step 5: Use Logical Log Records Example Manual Recovery Page IBM Informix STAR Conguration Parameters IBM Informix STAR Conguration Parameters DEADLOCK TIMEOUT TXTIME-OUT Track a Transaction with tbstat Output Tracking a Global Transaction Transaction address Field Transaction ag Field Transaction user Field Transaction locks Field Transaction log begin Transaction isolation Field Transaction retries Field Transaction coordinator Field A Appendix Notices Page Page Trademarks Trademarks Index Index A B 2IBM Informix OnLine Database Server Administrators Guide Index 3 C 4IBM Informix OnLine Database Server Administrators Guide D Index 5 E 6IBM Informix OnLine Database Server Administrators Guide F G H I Index 7 L 8IBM Informix OnLine Database Server Administrators Guide Index 9 M 10 IBM Informix OnLine Database Server Administrators Guide O P Index 11 Q R S 12 IBM Informix OnLine Database Server Administrators Guide T Index 13 14 IBM Informix OnLine Database Server Administrators Guide U Index 15 V W X Symbols