InfoScale™ 9.0 Storage and Availability Management for DB2 Databases - AIX, Linux
- Section I. Storage Foundation High Availability (SFHA) management solutions for DB2 databases
- Overview of Storage Foundation for Databases
- Introducing Storage Foundation High Availability (SFHA) Solutions for DB2
- About the File System component
- About the Volume Manager component
- About Dynamic Multi-Pathing (DMP)
- About Cluster Server
- About Cluster Server agents
- About InfoScale Operations Manager
- Feature support for DB2 across InfoScale products
- Use cases for InfoScale products
- Overview of Storage Foundation for Databases
- Section II. Deploying DB2 with InfoScale products
- Deployment options for DB2 in a Storage Foundation environment
- DB2 deployment options in an InfoScale environment
- DB2 on a single system with Storage Foundation
- DB2 on a single system with off-host in a Storage Foundation environment
- DB2 in a highly available cluster with Storage Foundation High Availability
- DB2 in a parallel cluster with SF Cluster File System HA
- Deploying DB2 and Storage Foundation in a virtualization environment
- Deploying DB2 with Storage Foundation SmartMove and Thin Provisioning
- Deploying DB2 with Storage Foundation
- Deploying DB2 in an off-host configuration with Storage Foundation
- Deploying DB2 with High Availability
- Deployment options for DB2 in a Storage Foundation environment
- Section III. Configuring Storage Foundation for Database (SFDB) tools
- Configuring and managing the Storage Foundation for Databases repository database
- About the Storage Foundation for Databases (SFDB) repository
- Requirements for Storage Foundation for Databases (SFDB) tools
- Storage Foundation for Databases (SFDB) tools availability
- Configuring the Storage Foundation for Databases (SFDB) tools repository
- Updating the Storage Foundation for Databases (SFDB) repository after adding a node
- Updating the Storage Foundation for Databases (SFDB) repository after removing a node
- Removing the Storage Foundation for Databases (SFDB) repository
- Configuring authentication for Storage Foundation for Databases (SFDB) tools
- Configuring and managing the Storage Foundation for Databases repository database
- Section IV. Improving DB2 database performance
- About database accelerators
- Improving database performance with Quick I/O
- About Quick I/O
- How Quick I/O improves database performance
- Tasks for setting up Quick I/O in a database environment
- Preallocating space for Quick I/O files using the setext command
- Accessing regular VxFS files as Quick I/O files
- Converting DB2 containers to Quick I/O files
- About sparse files
- Displaying Quick I/O status and file attributes
- Extending a Quick I/O file
- Monitoring tablespace free space with DB2 and extending tablespace containers
- Recreating Quick I/O files after restoring a database
- Disabling Quick I/O
- Improving DB2 database performance with VxFS Concurrent I/O
- Section V. Using point-in-time copies
- Understanding point-in-time copy methods
- About point-in-time copies
- When to use point-in-time copies
- About Storage Foundation point-in-time copy technologies
- Point-in-time copy solutions supported by SFDB tools
- About snapshot modes supported by Storage Foundation for Databases (SFDB) tools
- Volume-level snapshots
- Storage Checkpoints
- Considerations for DB2 point-in-time copies
- Administering third-mirror break-off snapshots
- Administering Storage Checkpoints
- About Storage Checkpoints
- Database Storage Checkpoints for recovery
- Creating a Database Storage Checkpoint
- Deleting a Database Storage Checkpoint
- Mounting a Database Storage Checkpoint
- Unmounting a Database Storage Checkpoint
- Creating a database clone using a Database Storage Checkpoint
- Restoring database from a Database Storage Checkpoint
- Gathering data for offline-mode Database Storage Checkpoints
- Backing up and restoring with Netbackup in an SFHA environment
- Understanding point-in-time copy methods
- Section VI. Optimizing storage costs for DB2
- Section VII. Storage Foundation for Databases administrative reference
- Storage Foundation for Databases command reference
- Tuning for Storage Foundation for Databases
- Troubleshooting SFDB tools
About the File System intent log
Most file systems rely on full structural verification by the fsck utility as the only means to recover from a system failure. For large disk configurations, this involves a time-consuming process of checking the entire structure, verifying that the file system is intact, and correcting any inconsistencies. The File System component (VxFS) provides fast recovery with the VxFS intent log and VxFS intent log resizing features.
VxFS reduces system failure recovery times by tracking file system activity in the VxFS intent log. This feature records pending changes to the file system structure in a circular intent log. The intent log recovery feature is not readily apparent to users or a system administrator except during a system failure. By default, VxFS file systems log file transactions before they are committed to disk, reducing time spent recovering file systems after the system is halted unexpectedly.
During system failure recovery, the VxFS fsck utility performs an intent log replay, which scans the intent log and nullifies or completes file system operations that were active when the system failed. The file system can then be mounted without requiring a full structural check of the entire file system. Replaying the intent log might not completely recover the damaged file system structure if there was a disk hardware failure; hardware problems might require a complete system check using the fsck utility provided with VxFS.
The mount command automatically runs the VxFS fsck command to perform an intent log replay if the mount command detects a dirty log in the file system. This functionality is only supported on a file system mounted on a Volume Manager (VxVM) volume, and is supported on cluster file systems.
See the fsck_vxfs(1M) manual page and mount_vxfs(1M) manual page.
The VxFS intent log is allocated when the file system is first created. The size of the intent log is based on the size of the file system - the larger the file system, the larger the intent log. You can resize the intent log at a later time by using the fsadm commnad.
See the fsadm_vxfs(1M) manual page.
The maximum default intent log size for disk layout Version 7 or later is 256 megabytes.
Note:
Inappropriate sizing of the intent log can have a negative impact on system performance.