Weirdly jumping TX rate and CCQ on a single device

bart613 · Tue May 19, 2015 1:59 am

Hi everyone,

Last year I bought RB 411GL with MikroTik R52nM 802.11a/b/g/n miniPCI Card card (and 2x 2.4-5.8GHz Omnidirectional Swivel Antenna with cable and MMCX connector) to use as a AP at home.

It took me a while, but going through the forums I managed to find quite optimal settings for my MT AP so I was able to easily push down / up ~ 20MB/s of raw transfer.

I was using this MT AP mostly with Apple devices (2x iPhone 6, 2x iPad, 2x Macbook).

Now, few weeks back I got a brand new Macbook Retina 13" early 2015 model. Since then I started having weird wireless performance problems only on that specific Macbook. I've got further two Retinas at home - no problems; they connect at over 260Mbps TX/RX with over 150000 IP throughput.

This one however, according to MT out gets really high RX rate - ~ 130Mbps and is rock-solid, TX rate however - just as CCQ on TX (from MT AP to the laptop) is jumping like crazy.

 0 interface=wlan1 mac-address=A4:5E:60:D0:3B:BD ap=no wds=no bridge=no rx-rate="130Mbps-20MHz/2S" tx-rate="26Mbps-20MHz/1S" packets=8212,10287
   bytes=4381322,1829036 frames=6156,10290 frame-bytes=4429498,1767657 hw-frames=34524,15494 hw-frame-bytes=27083273,2304121 tx-frames-timed-out=0
   uptime=8m47s last-activity=0ms signal-strength=-54dBm@24Mbps signal-to-noise=59dB signal-strength-ch0=-56dBm signal-strength-ch1=-59dBm evm-ch0=30
   evm-ch1=10 strength-at-rates=-53dBm@6Mbps 2s930ms,-54dBm@24Mbps 0ms,-54dBm@HT20-4 41s840ms,-54dBm@HT20-7 0ms tx-ccq=62% p-throughput=4877
   last-ip=10.17.17.41 802.1x-port-enabled=yes authentication-type=wpa2-psk encryption=aes-ccm group-encryption=aes-ccm management-protection=no
   wmm-enabled=yes tx-rate-set="OFDM:6-54 BW:1x-2x SGI:2x HT:0-15"

 0 interface=wlan1 mac-address=A4:5E:60:D0:3B:BD ap=no wds=no bridge=no rx-rate="130Mbps-20MHz/2S" tx-rate="30Mbps-40MHz/2S/SGI" packets=8229,10309
   bytes=4387056,1831075 frames=6173,10312 frame-bytes=4435266,1769564 hw-frames=35107,15566 hw-frame-bytes=27307329,2308108 tx-frames-timed-out=0
   uptime=8m51s last-activity=0ms signal-strength=-54dBm@24Mbps signal-to-noise=59dB signal-strength-ch0=-56dBm signal-strength-ch1=-58dBm evm-ch0=28
   evm-ch1=9 strength-at-rates=-53dBm@6Mbps 7s120ms,-54dBm@24Mbps 0ms,-54dBm@HT20-4 46s30ms,-53dBm@HT20-7 0ms tx-ccq=42% p-throughput=2968
   last-ip=10.17.17.41 802.1x-port-enabled=yes authentication-type=wpa2-psk encryption=aes-ccm group-encryption=aes-ccm management-protection=no
   wmm-enabled=yes tx-rate-set="OFDM:6-54 BW:1x-2x SGI:2x HT:0-15"

 0 interface=wlan1 mac-address=A4:5E:60:D0:3B:BD ap=no wds=no bridge=no rx-rate="130Mbps-20MHz/2S" tx-rate="6Mbps" packets=8369,10521 bytes=4422835,1862737
   frames=6300,10524 frame-bytes=4471532,1799954 hw-frames=38098,15985 hw-frame-bytes=28469271,2351946 tx-frames-timed-out=0 uptime=9m10s last-activity=0ms
   signal-strength=-53dBm@24Mbps signal-to-noise=60dB signal-strength-ch0=-55dBm signal-strength-ch1=-57dBm evm-ch0=28 evm-ch1=9
   strength-at-rates=-51dBm@6Mbps 3s10ms,-53dBm@24Mbps 0ms,-54dBm@HT20-4 1m4s910ms,-53dBm@HT20-7 0ms tx-ccq=36% p-throughput=4287 last-ip=10.17.17.41
   802.1x-port-enabled=yes authentication-type=wpa2-psk encryption=aes-ccm group-encryption=aes-ccm management-protection=no wmm-enabled=yes
   tx-rate-set="OFDM:6-54 BW:1x-2x SGI:2x HT:0-15"

These readings were taken literally 2 seconds apart - yet if you look at TX rate and CCQ they're massively different each time. This obviously results in absolutely horrible download speed on my new laptop as well as horribly jittery transmission of any form (upload, weirdly, works quite well most of the time).

Other laptops connected to the same MT AP have got rock-solid TX/RX rates and CCQ locked at 99%.

My Wireless interface settings are as follows:

[admin@MikroTik] > interface wireless print advanced
Flags: X - disabled, R - running
 0  R name="wlan1" mtu=1500 mac-address=D4:CB:6D:14:E9:13 arp=enabled disable-running-check=no interface-type=Atheros AR92xx radio-name="GOAWAY"
      mode=ap-bridge ssid="ML" area="" frequency-mode=regulatory-domain country=united kingdom antenna-gain=4 frequency=5620 band=5ghz-a/n
      channel-width=20/40mhz-eC scan-list=default wireless-protocol=802.11 rate-set=default supported-rates-b=1Mbps,2Mbps,5.5Mbps,11Mbps
      supported-rates-a/g=6Mbps,9Mbps,12Mbps,18Mbps,24Mbps,36Mbps,48Mbps,54Mbps basic-rates-b=1Mbps basic-rates-a/g=6Mbps max-station-count=2007
      distance=indoors tx-power=4 tx-power-mode=all-rates-fixed noise-floor-threshold=default nv2-noise-floor-offset=default dfs-mode=none vlan-mode=no-tag
      vlan-id=1 wds-mode=disabled wds-default-bridge=none wds-default-cost=100 wds-cost-range=50-150 wds-ignore-ssid=no update-stats-interval=disabled
      bridge-mode=enabled default-authentication=yes default-forwarding=yes default-ap-tx-limit=0 default-client-tx-limit=0
      proprietary-extensions=pre-2.9.25 wmm-support=enabled hide-ssid=no security-profile=default disconnect-timeout=15s on-fail-retry-time=100ms
      preamble-mode=long compression=no allow-sharedkey=no station-bridge-clone-mac=00:00:00:00:00:00 ampdu-priorities=0 guard-interval=any
      ht-supported-mcs=mcs-0,mcs-1,mcs-2,mcs-3,mcs-4,mcs-5,mcs-6,mcs-7,mcs-8,mcs-9,mcs-10,mcs-11,mcs-12,mcs-13,mcs-14,mcs-15,mcs-16,mcs-17,mcs-18,mcs-19,mcs-
                 20,mcs-21,mcs-22,mcs-23
      ht-basic-mcs=mcs-12,mcs-13,mcs-14,mcs-15 tx-chains=0,1 rx-chains=0,1 amsdu-limit=8192 amsdu-threshold=8192 tdma-period-size=2 nv2-queue-count=2
      nv2-qos=default nv2-cell-radius=30 nv2-security=disabled nv2-preshared-key="" hw-retries=15 frame-lifetime=0 adaptive-noise-immunity=client-mode
      hw-fragmentation-threshold=disabled hw-protection-mode=rts-cts hw-protection-threshold=0 frequency-offset=0 rate-selection=advanced
      multicast-helper=disabled multicast-buffering=enabled keepalive-frames=enabled

Now, my first thought after looking into this closer was "buggered WiFi card in laptop" HOWEVER at work we've got a pretty good setup based on Cisco Aironet devices and I don't have any issues using WiFi there. I get easily 12MB/s of raw transfer without any issues both sides and connection is rock-solid.

Please please please to chip in and follow up with any advice you've - I'm literally beginning to get grey because of this issue.

ps. Running 6.28

suntelSean · Tue May 19, 2015 4:02 am

Which wifi package is installed?

Sent from my iPhone using Tapatalk

Tue May 19, 2015 8:00 am

I do not know macs but I would be suspecting some power management feature of the notebook card. Try to fiddle around its driver's settings to elaborate more.