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AdministeringIn addition to administering the database server, you can tune performance, replicate data, and archive data.
System administrationThese topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL OneDB™ database servers.
Administrator's GuideThe HCL OneDB™ Administrator's Guide provides the information required to administer HCL OneDB™.
Disk, memory, and process management
Virtual processors and threadsThese topics describe virtual processors, explain how threads run within the virtual processors, and explain how the database server uses virtual processors and threads to improve performance.
Virtual processor classesEach class of virtual processor is dedicated to processing certain types of threads.
Disk I/O virtual processorsThe following classes of virtual processors perform disk I/O: PIO (physical-log I/O), LIO (logical-log I/O), AIO (asynchronous I/O), and CPU (kernel-asynchronous I/O).

Disk I/O virtual processors

The following classes of virtual processors perform disk I/O: PIO (physical-log I/O), LIO (logical-log I/O), AIO (asynchronous I/O), and CPU (kernel-asynchronous I/O).

The PIO class performs all I/O to the physical-log file, and the LIO class performs all I/O to the logical-log files, unless those files are in raw disk space and the database server has implemented KAIO.

On operating systems that do not support KAIO, the database server uses the AIO class of virtual processors to perform database I/O that is not related to physical or logical logging.

The database server uses the CPU class to perform KAIO when it is available on a platform. If the database server implements KAIO, a KAIO thread performs all I/O to raw disk space, including I/O to the physical and logical logs.

UNIX only: To find out if your UNIX™ platform supports KAIO, see the machine notes file.

Windows only: Windows™ supports KAIO.

For more information about nonlogging I/O, see Asynchronous I/O.

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