On Fri, 2016-10-21 at 13:03 -0500, Zach Brown wrote: > Is there a way to get NAPI to poll all the time? > Or just any way to get netdevices to use only polling and no interrupts? > > We have some rt targets where the jitter can be improved by disabling > interrupts and using just polling. In these cases we're okay with the > performance downsides that come with polling. > > In particular we already have an implementation for the cadence macb driver > that does only polling mode and have verified that it improves the > jitter. > > We're hoping for a more general existing solution or at the very least a > solution that would be accepted upstream. Any thoughts?
This is not yet done, although you could use busy poll infrastructure to get this without a kernel change. Open as many TCP flows are necessary to traverse all the queues you care about, then loop on recvmsg() to trigger NAPI polling.