Re: [PATCH v3 net-next 0/4] net: low latency Ethernet device polling

From: Eliezer Tamir
Date: Tue May 21 2013 - 08:29:38 EST

Many of the questions you asked are covered in our RFC cover letter, but I will touch them briefly

On 21/05/2013 15:06, Alex Rosenbaum wrote:
1. It seem this patch does not cover epoll/select and such IO muxing APIs?

We are thinking about how to implement epoll support as one of the next steps.

What benchmarks are you using to test poll/select/epoll?

2. How is the logic aware of RSS and RFS?

With TCP sockets, the driver knows the specific ring it need to poll so
this should be mapped and provide the best latency.

This code is blissfully oblivious of RFS and RSS, it only assumes that the packets for a socket are likely to continue to come on the same queue.
The code is designed to be correct even if you get your data on the wrong queue. (your performance will suffer but no more than that.)

3. I could not find any reference to multi-thread on single core logic.
This can causes the opposite effect and create contentions and higher

Again, the only bad thing that will happen if you misconfigure this is a performance hit, we will not deadlock.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at