Hi Thomas > -----Original Message----- > From: Thomas Monjalon [mailto:thomas.monjalon at 6wind.com] > Sent: Monday, November 3, 2014 3:50 PM > To: Zhang, Helin > Cc: dev at dpdk.org > Subject: Re: [dpdk-dev] [PATCH v5 1/5] i40e: Use constant random hash keys > > Hi Helin, > > The title is a bit surprising: > - it should be about RSS RSS makes use of hash function to route received packets, though hash function can be used for other cases, e.g. Flow director.
> - a constant cannot be really random ;) The hash keys are generated by libc random function. It is preparatory to avoid calling random function for each port. > > 2014-10-21 11:14, Helin Zhang: > > To be simpler, and remove the race condition, it uses prepared > > constant random hash keys to replace runtime generating the hash keys. > > Could you explain what is the role of rss_key_default? Hash function needs to be configured with keys, before end users configured them with specific keys, we need to provide a default keys which is generated by libc random function. The random keys can get the hash function to route the received packets to all the queues well-proportioned. > > Thanks > -- > Thomas Regards, Helin
