Re: 2.6.38: rt2800usb: high latency (1000ms)?

[Igor Plyatov]

Dear Daniel,
> On Wed, Apr 13, 2011 at 1:13 PM, Justin Piszcz<jpiszcz@xxxxxxxxxxxxxxx>  wrote:
> > > (1) What is the AP's beacon period and DTIM? Typical values are 100
> > > TUs for beacons (102.4 ms) and 2 for DTIM (2 beacons per power-save
> > > wakeup) which should imply a mean of 100 and max of 200 ms delay even
> > > on pings.
> > I am using a WNDR3700 with default settings in terms of beacons/etc.  No
> > issues with any device (laptop, computer, etc (in windows)), I have two
> > wireless USB adapters (bought two) and in Windows, no problems, I don't
> > think
> > it is the WNDR3700.  As far as linux/wpa-supplicant, using default settings.
> Not enough info. What does "iw dev wlan1 scan dump"  (it might not be
> wlan1 for you) say for "beacon interval"?
>
> Does anyone know how to get the DTIM period out of iw?
# iw dev wlan0 scan dump
BSS 74:ea:3a:e4:fa:6e (on wlan0) -- associated
    TSF: 499843461 usec (0d, 00:08:19)
    freq: 2442
    beacon interval: 100
    capability: ESS Privacy ShortPreamble ShortSlotTime (0x0431)
    signal: -51.00 dBm
    last seen: 510 ms ago
    Information elements from Probe Response frame:
    SSID: mynet2
    Supported rates: 1.0* 2.0* 5.5* 11.0* 6.0 9.0 12.0 18.0
    DS Parameter set: channel 7
    RSN:     * Version: 1
         * Group cipher: CCMP
         * Pairwise ciphers: CCMP
         * Authentication suites: PSK
         * Capabilities: (0x0000)
    ERP: <no flags>
    Extended supported rates: 24.0 36.0 48.0 54.0
    WMM:     * Parameter version 1
         * u-APSD
         * BE: CW 15-1023, AIFSN 3
         * BK: CW 15-1023, AIFSN 7
         * VI: CW 7-15, AIFSN 2, TXOP 3008 usec
         * VO: acm CW 3-7, AIFSN 2, TXOP 1504 usec
    HT capabilities:
        Capabilities: 0x104e
            HT20/HT40
            SM Power Save disabled
            RX HT40 SGI
            No RX STBC
            Max AMSDU length: 3839 bytes
            DSSS/CCK HT40
        Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
        Minimum RX AMPDU time spacing: 8 usec (0x06)
        HT RX MCS rate indexes supported: 0-15
        HT TX MCS rate indexes are undefined
    WPS:     * Version: 1.0
         * Wi-Fi Protected Setup State: 2 (Configured)
         * Response Type: 3 (AP)
         * Unknown TLV (0x1047, 16 bytes): 00 00 00 00 00 00 10 00 00 
00 74 ea 3a e4 fa 6e
         * Manufacturer: TP-LINK
         * Model: TL-WR1043N
         * Model Number: 1.0
         * Serial Number: 1.0
         * Primary Device Type: 6-0050f204-1
         * Device name: Wireless Router TL-WR1043N
         * Config methods: Ethernet, Label, PBC
         * RF Bands: 0x1

> > > (2) How long does the client wait after waking up to go back to sleep?
> > > It should be at least a few seconds. For ssh, then, you should see
> > > something like a 100-200 ms delay for the first key and then nothing
> > > at all unless you stop typing for a bit.
> > It lags with each word I type, it is terrible.  If I run something like
> > dmesg or ps auxww, the entire session freezes for 5-10 seconds before it
> > comes back.
> Sorry; I meant what is the software stack configured to do? Do some
> looking around.
What do you mean here?

Best regards!
--
Igor Plyatov
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