On Sun, Jan 11, 2015 at 10:23 PM, Chris Clayton <chris2553@xxxxxxxxxxxxxx> wrote: > Thanks Emmanuel. > > On 01/11/15 14:16, Emmanuel Grumbach wrote: >> Hi Chris, >> >> thank you for you analysis, it is very helpful >> > > You're welcome. > >>> Doh! Cut and paste error ... >>> >>> On 01/11/15 12:56, Chris Clayton wrote: >>>> Hi Kalle, >>>> >>>> Having recently bought a new laptop, I've just started using the iwlwifi driver for wireless networking. I found both >>>> 3.18.x and the current development tree to be very unreliable due to frequent disconnections from the router. >>>> >>>> Before you merged them into your tree, I grabbed the latest fixes from iwlwifi-fixes tree and applied them to the >>>> development kernel. Since I did that I've had no problems at all with dropped connections. I then looked at each patch >>>> to see whether it might be applicable to 3.18 and found that two of them looked as if they should be useful. They are: >>>> >>>> c93edc639392df733c7d72db4376a9add775d18a - iwlwifi: mvm: don't allow diversity if BT Coex / TT forbid it >>> >>> The above should have been: >>> >>> c93edc639392df733c7d72db4376a9add775d18a - iwlwifi: mvm: fix Rx with both chains >>> >>>> >>>> a9dc5060bf3a32ac3dad472f15416054b92dc5b5 - iwlwifi: mvm: fix out of bounds access to tid_to_mac80211_ac >>>> >>>> With those two applied, I've had stable wireless networking on 3.18.2 and, more recently, 3.18.2. Consequently, they >>>> seem appropriate for tagging for 3.18-stable, but, as far as I can see, they haven't been tagged for stable. Apologies, >>>> if I'm mistaken, but if I'm not, could you consider submitting the two patches for inclusion in 3.18, please? Of course, >>>> they may be appropriate to earlier kernels too - I haven't looked. >>>> >> >> The first one (c93edc639392df733c7d72db4376a9add775d18a) is tagged for stable. > > Ah, sorry I missed that. > >> Are you using bluetooth? > > Yes, I have a bluetooth mouse and use bluetooth for audio from time to time. > >> Are you able to tell me which of the two really helps? > > It's c93edc639392df733c7d72db4376a9add775d18a that helps. With that applied, I can set off a task which, in a loop, > continually copies a 180MB file from a server on my network. The network remained stable for over 30 minutes before I > killed the task. Without the patch, the network fails during the first iteration of copying the file. > > a9dc5060bf3a32ac3dad472f15416054b92dc5b5 doesn't seem to have any effect on the instability. Ok - I am not surprised - thanks. c93edc... allows to use 2 antennas instead of one only. Technically, one would be enough, but apparently, in your configuration, using 2 antennas allows to improve reliability. > > >> Unless I am missing something, the first one >> (c93edc639392df733c7d72db4376a9add775d18a) should help only if you >> disabled power save. Is that the case? > > Not that I know of. The only power-related thing in my init scripts is echoing 5 to /proc/sys/vm/laptop_mode, which I > believe configures disk activity to save power. The mouse does have a power saving feature, however. According to the > manual, it reduces its power consumption in steps the longer it is inactive. As I frequently work in kde's konsole > terminal application, mouse inactivity is common. > > Hope this helps and feel free to request additional information. Ok - I checked the code and we enable the redundancy mentioned above (2 antenna instead of 1) even if power save is enabled. FWIW - this redundancy is also called "diversity". Thanks. > > Chris >> -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
