Hi, On Fri, Jan 02, 2015 at 02:56:36PM -0800, Dave Taht wrote: > On Fri, Jan 2, 2015 at 11:03 AM, Felipe Balbi <balbi@xxxxxx> wrote: > > Hi, > > > > (please use reply-all to keep mailing lists in Cc, also avoid > > top-posting) > > I am trying not to read netdev right now... and failing, obviously. oops :-) > > On Fri, Jan 02, 2015 at 10:58:29AM -0800, Dave Taht wrote: > >> The beaglebone only has a 100mbit phy, so you aren't going to get more > >> than that. > > > > very true :-) Still, with AM437x SK which is definitely GigE, I'm > > getting 201Mbits/sec. > > > >> (so do a lot of IoT devices). > >> > >> So you have the two patches that went by on BQL and on NAPI for the beagle? > > > > no, got any pointers ? > > the relevant thread was "am335x: cpsw: phy ignores max-speed setting" > > and the initial very small BQL enablement patch was here: > > https://patchwork.ozlabs.org/patch/407640/ I'll test it out, sure. > (it needed a saner treatment of a failure to dma something in > cpsw_tx_packet_submit - the patch as is has also been part of nelsons > trees for the beaglebone for a while) > > But it was rightly pointed out later in the thread that this change > > +#define CPSW_POLL_WEIGHT 16 > > made for the biggest part of the improvement, and someone else on the > thread proposed handling that more dynamically for 100mbit phys with > another patch (that I can't find at the moment) > > ... but the root cause of the excessive latency in this driver was the > single tx/rx dma queue, which you are addressing in your patch set. I still think there's a lot of work pending for CPSW, the think slows to a crawl and takes a lot of CPU for something that should be mostly handled by DMA. I can very easily get 85% CPU usage with iperf. > So if you glop on more of the above, mo better, perhaps you will win > bigger. > > I will try to slice out some time to boot up a beagle on net-next next week. my patches aren't applied yet, however. cheers -- balbi
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