Hi, have a problem that bugs me for years, no solution found yet:
Two clients with Linux, same update status:
1. SLOW: Libretrend i7 with Coreboot, Realtek NIC
2. FAST: Old Dell Precision M6500 notebook with Intel NIC.
Problem: when downloading e.g. updates, the FAST ist 30-times faster than SLOW, see attached.
Same mirrors,RJ45 cables changed twice, both attached to the same switch. So no real explanation.
Yesterday I did some iperf between the two clients.
For UDP, it does not matter, which is server and whicch is client:
20260118145326,SLOW,FAST,45678,1,0.0-30.0,3935190,1048952,0.025,0,2677,0.000,0
20260118145446,FAST,SLOW,45678,1,0.0-30.0,3935190,1048950,-nan,0,-1,-0.000,0
But for TCP direction matters:
20260118144505,SLOW,FAST,45678,1,0.0-30.0,3533963328,941434163
20260118144740,FAST,SLOW,45678,1,0.0-30.1,1690173504,449722645
-------------------------
First thought: RJ45 in SLOW machine is Realtek. But I have Realtek in other machines with same linux, always maxing out the bandwith possible. So I don't think it'S simply Realtek.
Why only TCP makes a difference? Is there offloading and that doesn't work properly in the SLOW machine? Maybe due to Coreboot?
Any ideas how this difference in TCP-speed might be explainable?
:-)
Two clients with Linux, same update status:
1. SLOW: Libretrend i7 with Coreboot, Realtek NIC
2. FAST: Old Dell Precision M6500 notebook with Intel NIC.
Problem: when downloading e.g. updates, the FAST ist 30-times faster than SLOW, see attached.
Same mirrors,RJ45 cables changed twice, both attached to the same switch. So no real explanation.
Yesterday I did some iperf between the two clients.
For UDP, it does not matter, which is server and whicch is client:
20260118145326,SLOW,FAST,45678,1,0.0-30.0,3935190,1048952,0.025,0,2677,0.000,0
20260118145446,FAST,SLOW,45678,1,0.0-30.0,3935190,1048950,-nan,0,-1,-0.000,0
But for TCP direction matters:
20260118144505,SLOW,FAST,45678,1,0.0-30.0,3533963328,941434163
20260118144740,FAST,SLOW,45678,1,0.0-30.1,1690173504,449722645
-------------------------
First thought: RJ45 in SLOW machine is Realtek. But I have Realtek in other machines with same linux, always maxing out the bandwith possible. So I don't think it'S simply Realtek.
Why only TCP makes a difference? Is there offloading and that doesn't work properly in the SLOW machine? Maybe due to Coreboot?
Any ideas how this difference in TCP-speed might be explainable?
:-)
"