EF_SPIN_USEC

Onload User Guide (UG1586)

Document ID
UG1586
Release Date
2023-07-31
Revision
1.2 English
Name
ul_spin_usec
Default
0
Scope
per-process

Sets the timeout in microseconds for spinning options. Set this to -1 to spin forever. The spin timeout can also be set by the EF_POLL_USEC option.

Spinning typically reduces latency and jitter substantially, and can also improve throughput. However, in some applications spinning can harm performance, particularly application that have many threads. When spinning is enabled you should normally dedicate a CPU core to each thread that spins.

You can use the EF_*_SPIN options to selectively enable or disable spinning for each API and transport. You can also use the onload_thread_set_spin() extension API to control spinning on a per-thread and per-API basis.