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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).
Logical-log I/OThe LIO class of virtual processors performs I/O to the logical-log files.

Logical-log I/O

The LIO class of virtual processors performs I/O to the logical-log files.

I/O is performed to logical-log files in the following cases:

KAIO is not implemented.
The logical-log files are in cooked disk space.

Only when KAIO is implemented and the logical-log files are in raw disk space does the database server use a KAIO thread in the CPU virtual processor to perform I/O to the logical log.

The logical-log files store the data that enables the database server to roll back transactions and recover from system failures. I/O to the logical-log files is the highest priority disk I/O that the database server performs.

If the logical-log files are in a dbspace that is not mirrored, the database server runs only one LIO virtual processor. If the logical-log files are in a dbspace that is mirrored, the database server runs two LIO virtual processors. This class of virtual processors has no parameters associated with it.