slow on client side?

[Dario García]

hi

i recently started using tigerVNC and im facing some issues

it somehow is really really slow on the client side. for example moving windows is fluent on the server, but it feels like 10fps on the client. also sometimes connection seems to get interrupted, which causes missinputs. in some cases it will send a keypress without the release, resulting in spamming that key.

its a local connection via SSH, both PCs in the same room. ping is absolutely stable. im using linux (client: opensuse tumbleweed, server: archlabs linux) on both machines.

client command to connect:

vncviewer localhost:9900 -PreferredEncoding=tight -CompressLevel=8 -AutoSelect=0

server command:

x0vncserver -localhost -rfbauth ~/.vnc/passwd

i hope you can help me with this! thanks in advance

[Pierre Ossman]

Can you check which versions of TigerVNC are used at either end?

And what is the console output from x0vncserver? Perhaps it is stuck in
polling mode.

Regards
--
Pierre Ossman Software Development
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Phone: +46-13-214600

A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?

[Dario García]

hi pierre, thanks for your reply

im using v1.13.1 on both ends. i tested pinging again and noticed, that i was wrong about "absolutely stable". it is stable when i dont do anything, but the horrible lag i experience also shows in ping:

icmp_seq=151 Destination Host Unreachable

icmp_seq=151 Destination Host Unreachable

icmp_seq=151 Destination Host Unreachable

icmp_seq=151 Destination Host Unreachable

icmp_seq=151 Destination Host Unreachable

icmp_seq=151 Destination Host Unreachable

icmp_seq=151 Destination Host Unreachable

icmp_seq=152 ttl=64 time=1699 ms

it seems like, im pretty sure, its related to "a lot of stuff going on", moving windows but also scrolling textfiles in vim

x0vncserver output:

[Pierre Ossman]

On 5/25/23 20:28, Dario García wrote:
> hi pierre, thanks for your reply
>
> im using v1.13.1 on both ends. i tested pinging again and noticed, that i
> was wrong about "absolutely stable". it is stable when i dont do anything,
> but the horrible lag i experience also shows in ping:
>
> icmp_seq=151 Destination Host Unreachable
> icmp_seq=151 Destination Host Unreachable
> icmp_seq=151 Destination Host Unreachable
> icmp_seq=151 Destination Host Unreachable
> icmp_seq=151 Destination Host Unreachable
> icmp_seq=151 Destination Host Unreachable
> icmp_seq=151 Destination Host Unreachable
> icmp_seq=152 ttl=64 time=1699 ms
>
> it seems like, im pretty sure, its related to "a lot of stuff going on",
> moving windows but also scrolling textfiles in vim
>

I'm not surprised that TigerVNC has problems if the network is that bad.
TigerVNC tries very hard to not overload the network, though, so I'm
surprised it gets this bad.

You said the machines are in the same room, but are they on the same
network segment? Or is there a router or access point or something
between them?

[Dario García]

theres a wireless router in between server and client. i tested the VNC through my smartphones hotspot, just to make sure the router isnt causing the problem, but the result was the same

that wireless network normally works fine...the failed pings only seem to happen when using tigerVNC. i just did some speed/latency/packetloss tests on both machines and didnt encounter any problems

for now i changed the color level to 64 colors, which massively improved my experience. my impression is that the VNC connection in itself is stable, but somehow drops under bigger loads