Delays in ssh connections between two local Linux computers

[Shlomi Fish]

Hi Oleg,

On Mon, Sep 12, 2011 at 6:52 PM, Oleg Goldshmidt <pub at goldshmidt.org> wrote:
>
>
> On Mon, Sep 12, 2011 at 4:37 PM, Shlomi Fish <shlomif at gmail.com> wrote:
>>
>> Often when I type
>> commands on bash on the remote laptop via ssh, there is a significant
>> delay,
>> and moreover running claws-mail or gringotts (two fast gtk+ apps) from the
>> laptop are slow, which hadn't been the case with my older desktop machine.
>
> As far as I understand all of these go through ssh (with ssh redirecting
> X/gtk+ apps). Do you know if the problem is confined to ssh or is it a
> general network latency problem? If you set up some other kind of server
> (web?) and try to reach it - will you see slowness?

Well, I downloaded a large file using ssh from an HTTP service on the
laptop and it took a lot of time to connect but then downloaded at
11.2 MB/s.

>
> If you connect the laptop with a cable, do you still experience the problem?

I've now connected the laptop using an Ethernet cable and am still
getting this problem. I'm also getting it when ssh'ing from the laptop
to the main computer.

> What if you change the wireless channel?
>

Didn't try, but it also happens using a wired connection.

> Obviously, these are not solutions, but experimenting may help you focus on
> network vs. general network configuration vs. ssh configuration, etc.
>

To reply to shimi, I'm getting this ping trace:

[root at localhost ~]# ping 192.168.1.10
PING 192.168.1.10 (192.168.1.10) 56(84) bytes of data.
64 bytes from 192.168.1.10: icmp_req=3 ttl=64 time=0.315 ms
64 bytes from 192.168.1.10: icmp_req=7 ttl=64 time=0.258 ms
64 bytes from 192.168.1.10: icmp_req=8 ttl=64 time=0.313 ms
64 bytes from 192.168.1.10: icmp_req=9 ttl=64 time=0.258 ms
64 bytes from 192.168.1.10: icmp_req=10 ttl=64 time=0.330 ms
64 bytes from 192.168.1.10: icmp_req=11 ttl=64 time=0.296 ms
64 bytes from 192.168.1.10: icmp_req=13 ttl=64 time=0.293 ms
64 bytes from 192.168.1.10: icmp_req=14 ttl=64 time=0.284 ms
64 bytes from 192.168.1.10: icmp_req=15 ttl=64 time=0.288 ms
64 bytes from 192.168.1.10: icmp_req=18 ttl=64 time=0.281 ms
64 bytes from 192.168.1.10: icmp_req=19 ttl=64 time=0.265 ms
64 bytes from 192.168.1.10: icmp_req=20 ttl=64 time=0.279 ms
64 bytes from 192.168.1.10: icmp_req=21 ttl=64 time=0.273 ms
64 bytes from 192.168.1.10: icmp_req=22 ttl=64 time=0.501 ms
64 bytes from 192.168.1.10: icmp_req=23 ttl=64 time=0.499 ms
64 bytes from 192.168.1.10: icmp_req=24 ttl=64 time=0.309 ms
64 bytes from 192.168.1.10: icmp_req=25 ttl=64 time=0.270 ms
64 bytes from 192.168.1.10: icmp_req=28 ttl=64 time=0.301 ms

Seems like a lot of packets are dropped. Next, I will try to reboot
the laptop. Maybe it will help.

Regards,

-- Shlomi Fish

>
> --
> Oleg Goldshmidt | oleg at goldshmidt.org
>



-- 
------------------------------------------
Shlomi Fish http://www.shlomifish.org/

Electrical Engineering studies. In the Technion. Been there. Done
that. Forgot a lot. Remember too much.