Veritas InfoScale™ 7.4 Solutions Guide - Solaris
- Section I. Introducing Veritas InfoScale
- Section II. Solutions for Veritas InfoScale products
- Section III. Improving database performance
- Overview of database accelerators
- Improving database performance with Veritas Quick I/O
- About Quick I/O
- Improving database performance with Veritas Cached Quick I/O
- Improving database performance with Veritas Concurrent I/O
- Section IV. Using point-in-time copies
- Understanding point-in-time copy methods
- Backing up and recovering
- 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 V. Maximizing storage utilization
- Optimizing storage tiering with SmartTier
- Optimizing storage with Flexible Storage Sharing
- Optimizing storage tiering with SmartTier
- Section VI. Migrating data
- Understanding data migration
- Offline migration from Solaris Volume Manager to Veritas Volume Manager
- How Solaris Volume Manager objects are mapped to VxVM objects
- Overview of the conversion process
- Planning the conversion
- Preparing a Solaris Volume Manager configuration for conversion
- Setting up a Solaris Volume Manager configuration for conversion
- Converting from the Solaris Volume Manager software to VxVM
- Post conversion tasks
- Online migration of a native file system to the VxFS file system
- Migrating a source file system to the VxFS file system over NFS v3
- 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
- Displaying information
- File system considerations
- Specifying the migration target
- Using the fscdsadm command
- Maintaining the list of target operating systems
- Migrating a file system on an ongoing basis
- Converting the byte order of a file system
- Migrating from Oracle ASM to Veritas File System
- Section VII. Veritas InfoScale 4K sector device support solution
About Cached Quick I/O
Veritas Cached Quick I/O maintains and extends the database performance benefits of Veritas Quick I/O by making more efficient use of large, unused system memory through a selective buffering mechanism. Cached Quick I/O also supports features that support buffering behavior, such as file system read-ahead.
Enabling Cached Quick I/O on suitable Quick I/O files improves database performance by using the file system buffer cache to store data. This data storage speeds up system reads by accessing the system buffer cache and avoiding disk I/O when searching for information.
Having data at the cache level improves database performance in the following ways:
For read operations, Cached Quick I/O caches database blocks in the system buffer cache, which can reduce the number of physical I/O operations and therefore improve read performance.
For write operations, Cached Quick I/O uses a direct-write, copy-behind technique to preserve its buffer copy of the data. After the direct I/O is scheduled and while it is waiting for the completion of the I/O, the file system updates its buffer to reflect the changed data being written out. For online transaction processing, Cached Quick I/O achieves better than raw device performance in database throughput on large platforms with very large physical memories.
For sequential table scans, Cached Quick I/O can significantly reduce the query response time because of the read-ahead algorithm used by Veritas File System. If a user needs to read the same range in the file while the data is still in cache, the system is likely to return an immediate cache hit rather than scan for data on the disk.