EF_CTPIO_MAX_FRAME_LEN

Onload User Guide (UG1586)
Document ID
UG1586
Release Date
2023-07-31
Revision
1.2 English
Name
ctpio_max_frame_len
Default
500 if EF_CTPIO_MODE=ct, else 1518
Minimum
0
Maximum
4092
Scope
per-stack

Sets the maximum frame length for the CTPIO low-latency transmit mechanism. Packets up to this length will use CTPIO, if CTPIO is supported by the adapter and if CTPIO is enabled (see EF_CTPIO). Longer packets will use PIO and/or DMA. The cost per byte of packet payload varies between host architectures, as does the effect of packet size on the probability of poisoning, and so on some hosts it might be beneficial to reduce this value.