Gentoo Archives: gentoo-user

From: thelma@×××××××××××.com
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] network transfer speed
Date: Sat, 16 Jan 2021 20:36:27
Message-Id: 33c5a9af-5ac7-5159-1cd1-c1a38bd522e6@sys-concept.com
In Reply to: Re: [gentoo-user] network transfer speed by Adam Carter
1 On 1/15/21 9:00 PM, Adam Carter wrote:
2 >> On a remote network I run ethtool on both cards and I got both 1000Mb/s
3 >> speed
4 >>
5 >>
6 > As the 20 odd MB/s you're getting is above what is possible on 100M
7 > ethernet, you can rule out any ethernet interfaces at 100M.
8
9 1.) One Gentoo PC (that is about 20-30meters away from the switch) negotiated the speed of only 100 despite being capable of doing 1000.
10 I'll have to buy a new switch and make a new CAT5e cable to test it.
11 But but it will take some time.
12
13 > Can you describe the network between the two systems with the slow transfer?
14
15 2.) The two Gentoo PC that are meters away from the switch are my concern firs.
16 One is a server, another small PC run 24/7 and both negotiated speed of 1000 with the switch.
17
18 I have to re-test the transfer speed between these to boxes first, and check to light on the switch if it is green and/or orange
19
20 > If there is a fast WAN from one side of the globe to the other it could be
21 > latency related. OpenSSH used to have a fixed internal window size that
22 > made it slow on high bandwidth high latency links, and I notice the hpn USE
23 > flag still exists in the openssh ebuild, which implies the issue with
24 > openssh still exists. Rsync can use either ssh or its own protocol, so if
25 > there's a high latency link between the two boxes and rsync is using ssh,
26 > you could investigate rebuilding openssh with +hpn.
27 >
28 > What does ping show the latency as?
29 >
30 > Otherwise i'd be thinking about packet loss. First place to start for that
31 > is on the endpoint interfaces;
32 > ifconfig enp35s0f0 | grep err
33 > RX errors 0 dropped 0 overruns 0 frame 0
34 > TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
35
36 I'll test the above for errors tomorrow.

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Re: [gentoo-user] network transfer speed Jack <ostroffjh@×××××××××××××××××.net>