Hi Eric, First of all thank you for replying and giving some spotlight.
First step would be to read Documentation/networking/scaling.txt and see if anything there helps. - This is good article. I had gone through it. Any suggestion on RSS? How to configure it? Do I need to take care anything specially in my NIC driver? Have you tried to profile the kernel and see if some contention or hot function appears ? - I have added time stampings in different functions. That is how I came to know that almost ~3375 neno seconds are used by just " netif_receive_skb " don’t know why. With less than that time my DMA operation is finishes and descriptors are managed. Current time consuming function are " netif_receive_skb " and " napi_alloc_skb " these two function calls are taking maximum about of time Maybe use a faster cpu, or remove not needed features like too heavy netfilter rules. - I am using Intex Xeon Platinum series processors. These are fast enough CPUs available in market with 64 cores. 2 CPU nodes (each has 32 core) We can not really answer your question, you do not provide enough information. - Please let me know what additional details you need. We have 6 queues in HW. Each is mapped to MSI-X vector. Each vector is giving interrupt on different CPU. From interrupt I am scheduling napi and from napi poll function I am getting DMA page and constructing skb and passing it to network layer with "netif_receive_skb". Let me know additional details which are required. Regards, Keyur -----Original Message----- From: Eric Dumazet <eric.duma...@gmail.com> Sent: Thursday, October 25, 2018 10:38 PM To: Keyur Amrutbhai Patel <key...@xilinx.com>; netdev@vger.kernel.org Subject: Re: netif_receive_skb is taking long time EXTERNAL EMAIL On 10/25/2018 08:39 AM, Keyur Amrutbhai Patel wrote: > Hi, > > In my NIC driver "netif_receive_skb" is taking too long time. Almost 3375 > neno seconds. Which is more than whole packet processing from interrupt. > > Could anyone please help me to understand what could be the reason behind > this? How to solve it to take minimum time? > > Is there any standard calls which we need to follow in order to get faster > performance? > First step would be to read Documentation/networking/scaling.txt and see if anything there helps. Have you tried to profile the kernel and see if some contention or hot function appears ? Maybe use a faster cpu, or remove not needed features like too heavy netfilter rules. We can not really answer your question, you do not provide enough information.
