InfoScale™ 9.0 Solutions Guide - AIX
- Section I. Introducing InfoScale
- Section II. Solutions for InfoScale products
- Section III. Stack-level migration to IPv6 or dual stack
- Section IV. Improving database performance
- Overview of database accelerators
- Improving database performance with Quick I/O
- About Quick I/O
- Tasks for setting up Quick I/O in a database environment
- Creating DB2 database containers as Quick I/O files using qiomkfile Creating Sybase files as Quick I/O files using qiomkfile
- Preallocating space for Quick I/O files using the setext command
- Accessing regular VxFS files as Quick I/O files
- Extending a Quick I/O file
- Disabling Quick I/O
- Improving database performance with Cached Quick I/O
- Improving database performance with Concurrent I/O
- Section V. Using point-in-time copies
- Understanding point-in-time copy methods
- Backing up and recovering
- Storage Foundation and High Availability solutions backup and recovery methods
- Preserving multiple point-in-time copies
- Online database backups
- Backing up on an off-host cluster file system
- Database recovery using Storage Checkpoints
- Backing up and recovering in a NetBackup environment
- Off-host processing
- Creating and refreshing test environments
- Creating point-in-time copies of files
- Section VI. Maximizing storage utilization
- Optimizing storage tiering with SmartTier
- About SmartTier
- About VxFS multi-volume file systems
- About VxVM volume sets
- About volume tags
- SmartTier use cases for Sybase
- Setting up a filesystem for storage tiering with SmartTier
- Relocating old archive logs to tier two storage using SmartTier
- Relocating inactive tablespaces or segments to tier two storage
- Relocating active indexes to premium storage
- Relocating all indexes to premium storage
- Optimizing storage with Flexible Storage Sharing
- Optimizing storage tiering with SmartTier
- Section VII. Migrating data
- Understanding data migration
- Offline migration of native volumes and file systems to VxVM and VxFS
- About converting LVM, JFS and JFS2 configurations
- Initializing unused LVM physical volumes as VxVM disks
- Converting LVM volume groups to VxVM disk groups
- Volume group conversion limitations
- Conversion process summary
- Conversion of JFS and JFS2 file systems to VxFS
- Conversion steps explained
- Identify LVM disks and volume groups for conversion
- Analyze an LVM volume group to see if conversion is possible
- Take action to make conversion possible if analysis fails
- Back up your LVM configuration and user data
- Plan for new VxVM logical volume names
- Stop application access to volumes in the volume group to be converted
- Conversion and reboot
- Convert a volume group
- Take action if conversion fails
- Implement changes for new VxVM logical volume names
- Restart applications on the new VxVM volumes
- Tailor your VxVM configuration
- Restoring the LVM volume group configuration
- Examples of using vxconvert
- About test cases
- Converting LVM, JFS and JFS2 to VxVM and VxFS
- Online migration of native LVM volumes to VxVM volumes
- About online migration from Logical Volume Manager (LVM) volumes to VxVM volumes
- Online migration from LVM volumes in standalone environment to VxVM volumes
- Administrative interface for online migration from LVM in standalone environment to VxVM
- Preparing for online migration from LVM in standalone environment to VxVM
- Migrating from LVM in standalone environment to VxVM
- Reconfiguring the application to use VxVM volume device path
- Backing out online migration of LVM in standalone environment to VxVM
- Do's and Don'ts for online migration from LVM in standalone environment to VxVM
- Scenarios not supported for migration from LVM in standalone environment to VxVM
- Online migration from LVM volumes in VCS HA environment to VxVM volumes
- About online migration from LVM in VCS HA environment to VxVM
- Administrative interface for online migration from LVM in VCS HA environment to VxVM
- Preparing for online migration from LVM in VCS HA environment to VxVM
- Migrating from LVM in VCS HA environment to VxVM
- Migrating configurations with multiple volume groups
- Backing out online migration of LVM in VCS HA environment to VxVM
- Do's and Don'ts for online migration from LVM in VCS HA environment to VxVM
- Scenarios not supported for migration from LVM VCS HA environment to VxVM
- Online migration of a native file system to the VxFS file system
- About online migration of a native file system to the VxFS file system
- Administrative interface for online migration of a native file system to the VxFS file system
- Migrating a native file system to the VxFS file system
- Migrating a source file system to the VxFS file system over NFS v3
- Backing out an online migration of a native file system to the VxFS file system
- VxFS features not available during online migration
- Migrating storage arrays
- Migrating data between platforms
- Overview of the Cross-Platform Data Sharing (CDS) feature
- CDS disk format and disk groups
- Setting up your system to use Cross-platform Data Sharing (CDS)
- Maintaining your system
- Disk tasks
- Disk group tasks
- Changing the alignment of a disk group during disk encapsulation
- Changing the alignment of a non-CDS disk group
- Splitting a CDS disk group
- Moving objects between CDS disk groups and non-CDS disk groups
- Moving objects between CDS disk groups
- Joining disk groups
- Changing the default CDS setting for disk group creation
- Creating non-CDS disk groups
- Upgrading an older version non-CDS disk group
- Replacing a disk in a CDS disk group
- Setting the maximum number of devices for CDS disk groups
- Changing the DRL map and log size
- Creating a volume with a DRL log
- Setting the DRL map length
- Displaying information
- Determining the setting of the CDS attribute on a disk group
- Displaying the maximum number of devices in a CDS disk group
- Displaying map length and map alignment of traditional DRL logs
- Displaying the disk group alignment
- Displaying the log map length and alignment
- Displaying offset and length information in units of 512 bytes
- Default activation mode of shared disk groups
- Additional considerations when importing CDS disk groups
- File system considerations
- Considerations about data in the file system
- File system migration
- Specifying the migration target
- Using the fscdsadm command
- Checking that the metadata limits are not exceeded
- Maintaining the list of target operating systems
- Enforcing the established CDS limits on a file system
- Ignoring the established CDS limits on a file system
- Validating the operating system targets for a file system
- Displaying the CDS status of a file system
- Migrating a file system one time
- Migrating a file system on an ongoing basis
- When to convert a file system
- Converting the byte order of a file system
- Alignment value and block size
- Migrating a snapshot volume
- Section VIII. InfoScale 4K sector device support solution
Tasks for setting up Quick I/O in a database environment
Quick I/O is included in the VxFS package shipped with the InfoScale Foundation, InfoScale Storage, and InfoScale Enterprise products. By default, Quick I/O is enabled when you mount a VxFS file system.
If Quick I/O is not available in the kernel, or an InfoScale product license is not installed, a file system mounts without Quick I/O by default, the Quick I/O file name is treated as a regular file, and no error message is displayed. If, however, you specify the -o qio option, the mount command prints the following error message and terminates without mounting the file system.
VxFDD: You don't have a license to run this program vxfs mount: Quick I/O not available
To use Quick I/O, you must:
Preallocate files on a VxFS file system
Preallocating database files for Quick I/O allocates contiguous space for the files. The file system space reservation algorithms attempt to allocate space for an entire file as a single contiguous extent. When this is not possible due to lack of contiguous space on the file system, the file is created as a series of direct extents. Accessing a file using direct extents is inherently faster than accessing the same data using indirect extents. Internal tests have shown performance degradation in OLTP throughput when using indirect extent access. In addition, this type of preallocation causes no fragmentation of the file system.
You must preallocate Quick I/O files because they cannot be extended through writes using their Quick I/O interfaces. They are initially limited to the maximum size you specify at the time of creation.
Use a special file naming convention to access the files
VxFS uses a special naming convention to recognize and access Quick I/O files as raw character devices. VxFS recognizes the file when you add the following extension to a file name:
::cdev:vxfs:
Whenever an application opens an existing VxFS file with the extension ::cdev:vxfs: (cdev being an acronym for character device), the file is treated as if it were a raw device. For example, if the file temp01 is a regular VxFS file, then an application can access temp01 as a raw character device by opening it with the name:
.temp01::cdev:vxfs:
Note:
We recommend reserving the ::cdev:vxfs: extension only for Quick I/O files. If you are not using Quick I/O, you could technically create a regular file with this extension; however, doing so can cause problems if you later enable Quick I/O.
Depending on whether you are creating a new database or are converting an existing database to use Quick I/O, you have the following options:
If you are creating a new database to use Quick I/O:
You can use the qiomkfile command to preallocate space for database files and make them accessible to the Quick I/O interface.
You can use the setext command to preallocate space for database files and create the Quick I/O files.
If you are converting an existing database:
You can create symbolic links for existing VxFS files, and use these symbolic links to access the files as Quick I/O files.