Jump to content
Welcome to our new Citrix community!
  • 0

HDX Adaptive Transport/EDT over UDP High Latency/RTT vs TCP


Jon Via1709157340

Question

Hello, I have a remote user that is running Windows 10 1709, Receiver 4.10.1, connecting to a 7.13 VDA within our environment two devices.  The first device is an ASUS laptop, Intel graphics, 2560x1440 resolution.  This device connects using UDP (Adaptive Transport / EDT) with zero issues, RTT and Latency is around 30ms pretty consecutively.  The next device is in the same location, same wireless, its a workstation with Windows 10 1709, Receiver 4.10.1, connecting to the same 7.13 VDA.  It has an NVIDIA 1080 video card, external monitor (Alienware/Dell 34" Curved), connecting with UDP as well, however this device when idle shows 30ms, but once the user starts utilizing the session, it becomes almost unusable with RTT and Latency over 5,000ms.

 

Now, if Citrix receiver is forced out of HDXoverUDP with a 0 (via registry), user can connect over TCP with similar results as the laptop (30-32ms RTT/Latency).

 

Things we've tried, reformatting Windows, using multiple iterations for testing (lowering refresh rate, screen resolution, g-sync on and off, fixed frame rate, older NVIDIA drivers, rolling Citrix Receiver backwards), however nothing seems to resolve the UDP slowness issue.  We even tried connecting the PC directly to the modem (bypassing the entire wireless and wired network), still the issue remains.  Using Receiver 4.5 and below, works fine, 4.6 and above the issue occurs.

 

Also, other remote users that utilize UDP have no reported issues (or any found in Director).

 

Full PC system is:

 

CPU: Intel I7-7700k

GPU: NVIDIA 1080

Memory: 16GB

Wireless: 4x4 ASUS PCE-88U

 

OS: Windows 10 1709

Receiver: 4.10.1

 

TCP ctxsession.exe items:

 

Session  1 Transport Protocols: TCP -> CGP -> ICA
    Local Address:      **.**.**.**:2598
    Remote Address:     **.**.**.**:9860
    Client Address:     **.**.**.**:59404

    ICA Statistics (QoS Level 0):
        SentBandwidth (bps) =          0    RecvBandwidth (bps) =          0
        SentPreCompression  =     179540    RecvPreExpansion    =        705
        SentPostCompression =     177510    RecvPostExpansion   =       1529
        Compression Ratio % =         98    Expansion Ratio %   =         46
        LastLatency         =          0    AverageLatency      =          0

    ICA Statistics (QoS Level 1):
        SentBandwidth (bps) =      13304    RecvBandwidth (bps) =          0
        SentPreCompression  =   17841776    RecvPreExpansion    =     406307
        SentPostCompression =   15582268    RecvPostExpansion   =     338775
        Compression Ratio % =         87    Expansion Ratio %   =        119
        LastLatency         =         32    AverageLatency      =         31

    ICA Statistics (QoS Level 2):
        SentBandwidth (bps) =          0    RecvBandwidth (bps) =          0
        SentPreCompression  =        472    RecvPreExpansion    =        369
        SentPostCompression =        332    RecvPostExpansion   =        435
        Compression Ratio % =         70    Expansion Ratio %   =         84
        LastLatency         =          0    AverageLatency      =          0

    ICA Statistics (QoS Level 3):
        SentBandwidth (bps) =          0    RecvBandwidth (bps) =          0
        SentPreCompression  =      12191    RecvPreExpansion    =       5918
        SentPostCompression =        723    RecvPostExpansion   =      46350
        Compression Ratio % =          5    Expansion Ratio %   =         12
        LastLatency         =          0    AverageLatency      =          0

 

UDP ctxsession.exe items:

 

Session  1 Transport Protocols: UDP -> CGP -> ICA
    Local Address:      **.**.**.**:2598
    Remote Address:     **.**.**.**:5612
    Client Address:     **.**.**.**:60441

    EDT Statistics:
        Bandwidth 19545344 bps, RTT 37750 usec
        Flow Window 8191, Congestion Window 16
        Sent 3725, Rcvd 11068, Retransmitted 13
        Lost Sent 14, Lost Rcvd 579
        Sent ACKs 3506, NAKs 567, Rcvd ACKs 2526, NAKs 6

    ICA Statistics (QoS Level 0):
        SentBandwidth (bps) =      76456    RecvBandwidth (bps) =        320
        SentPreCompression  =    2411454    RecvPreExpansion    =      79895
        SentPostCompression =    2175246    RecvPostExpansion   =     109364
        Compression Ratio % =         90    Expansion Ratio %   =         73
        LastLatency         =       1181    AverageLatency      =       3038

Link to comment

3 answers to this question

Recommended Posts

  • 0

Although this doesn't help much, we actually experienced similar behavior and had to disable the EDT/UDP configuration and force everyone back to TCP. This was a big shame as we have staff all over the world, some with really poor links, including satellite, and were really keen to see what the performance was like.

 

We didn't really have time to narrow it down, but ironically it seemed to correlate with an actual degradation in the Internet connection. After a certain threshold, which wasn't much, ICA RTT + latency went through the roof. We originally thought it was the crappy ADSL modem but we had similar experiences with other Internet connections.

 

This was Receiver 4.9 with NSGW 12.0.53.13 and VDA 7.15 on Windows 10. It could be device related, hopefully we get some time to test this month.

Link to comment

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...