On 29 April 2016 at 19:12, Iñaki Pascual <[email protected]> wrote: > Hi, > > I am measuring TCP and UDP latency (actually RTT) and I am getting too high > values when working with channels with 40MHz (also with 80MHz) width. > > I am using hping3 for testing and these are the RTT avg values: > > BW 20 MHz: TCP 0.9 UDP 1.1 > BW 40 MHz: TCP 7.7 UDP 1.3 > BW 80 MHz: TCP 3.5 UDP 1.3
Just 2cc. Did you try changing the a-msdu/a-mpdu limits in firmware? You can tune it via debugfs file: echo 3 64 > /sys/kernel/debug/ieee80211/phy0/ath10k/htt_max_amsdu_ampdu The "3" stands for A-MSDU limit, "64" stands for A-MPDU limit. "3 64" is the default. You can test, e.g. - "1 64" - "3 8" - "1 1" - "1 8" And see if this changes TCP RTT in any way. You didn't really tell your setup (or I missed it). Are you using ath10k as AP, client, or both (i.e. have two ath10k supported devices)? Are you bridging traffic or is to locally generated? Perhaps there's a problem with hw offloaded ip/tcp checksumming. You might want to remove it from the driver (manually) to verify that or check tcpdump to confirm whether OTA frames have correct checksums. Michał _______________________________________________ ath10k mailing list [email protected] http://lists.infradead.org/mailman/listinfo/ath10k
