Table 11 shows the classes of virtual processors and the types of processing that they do. Each class of virtual processor is dedicated to processing certain types of threads.
| Virtual-
Processor Class |
Category | Purpose |
|---|---|---|
| CPU | Central processing | Runs all session threads and some system threads. Runs thread for kernel asynchronous I/O where available. Can run a single poll thread, depending on configuration. |
| PIO | Disk I/O | Writes to the physical-log file (internal class) if it is in cooked disk space. |
| LIO | Disk I/O | Writes to the logical-log files (internal class) if they are in cooked disk space. |
| AIO | Disk I/O | Performs nonlogging disk I/O. If kernel asynchronous I/O is used, AIO virtual processors perform I/O to cooked disk spaces. |
| SHM | Network | Performs shared memory communication. |
| TLI | Network | Uses the Transport Layer Interface (TLI) to perform network communication. |
| SOC | Network | Uses sockets to perform network communication. |
| OPT | Optical | Performs I/O to optical disk. |
| ADM | Administrative | Performs administrative functions. |
| FIF | FIFO I/O | Performs reads and inserts for high performance loading and unloading through FIFO (first-in-first-out) files. |
| MSC | Miscellaneous | Services requests for system calls that require a very large stack. |
| CSM | Communications
Support Module |
Performs communications support service operations. |