WiFi Latency Issues

[nachiketh]

So i'm running an rPi in an always on mode and connecting to it over the WiFi. I'm using a 0a12:0001 Cambridge Silicon Radio, Ltd Bluetooth Dongle (HCI mode) USB WiFi dongle which is one of the recommended peripherals. I'm seeing that the network latency from my laptop to the rPi is too high whereas the other way around seems acceptable.
Laptop:

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wlan0     IEEE 802.11abgn  ESSID:"XXXX"  
          Mode:Managed  Frequency:2.462 GHz  Access Point: XXXX 
          Bit Rate:1 Mb/s   Tx-Power=15 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=39/70  Signal level=-71 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:13  Invalid misc:2395   Missed beacon:0

RaspberryPi:

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wlan0     IEEE 802.11bgn  ESSID:"XXXX"  Nickname:"XXXX"
          Mode:Managed  Frequency:2.462 GHz  Access Point: XXXX   
          Bit Rate:150 Mb/s   Sensitivity:0/0  
          Retry:off   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=98/100  Signal level=23/100  Noise level=0/100
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

are there any tips or suggestions on how to improve the "Link Quality" between the two, please let me know!
Cheers!

[gerdesj]

The real test of signal quality is to use it. Any problems?

You asked the wrong question! You should have said: "my requirement is this xxxx but I only get this yyyy. How do I get xxxx closer to yyyy?"

Consider using iperf for a better idea of real world performance. I'll grant you that the docs are a little intimidating https://iperf.fr/iperf-doc.php but worth reading.

[nachiketh]

The real test of signal quality is to use it. Any problems?

Yes i'm facing packet drops between my laptop and pi and also delays in TCP communication, this is intermittent as most times the ping response seems ok and sometimes it is high, below is a snapshot, as you can see the min is 10 ms where as the max is a 1000 ms, I have even seen as high as 7000 ms sometimes.

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15 packets transmitted, 15 received, 0% packet loss, time 14025ms
rtt min/avg/max/mdev = 9.815/203.670/1196.734/273.861 ms, pipe 2