HP-UX 11i Tuning and Performance

13.5. Trade-offs with Network System Calls

This section describes important networking performance issues that application writers need to be familiar with in HP-UX.

13.5.1. Select and Poll System Calls

The select(2) and poll(2) system calls provide a way to see if a file descriptor has available work ready for reading or is available for writing. Unfortunately, the interface for both select and poll does not scale well when the number of file descriptors is large. This can be a problem when these are used in applications where potentially thousands of connections could be open at one time. It is therefore recommended that neither select nor poll are used when more than thirty file descriptors need to be managed at one time. See Section 13.5.2 ...