Congestion control concerns controlling traffic entry into a telecommunications network, so as to avoid congestive collapse by attempting to avoid oversubscription of any of the processing or link capabilities of the intermediate nodes and networks and taking resource reducing steps, such as reducing the rate of sending packets.
Questions tagged [congestion-control]
105 questions
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Enabling newreno in linux kernel
Can someone please give me pointers on enabling newReno in the linux kernel. Is the opensource source code available anywhere? I could get some cpp code online, but I would have to rewrite the whole thing to use it in linux kernel.
user3349765
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TCP congestion window size ..?
I am interested in getting congestion window size of a connection. The connection is created by another program. I am hoping that we can get this congestion window size using some file in proc, or, there is a call to get this info from kernel...
So…
nikhilelite
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trace congestion window of a particular TCP connection in the linux kernel
I am trying to trace the congestion window of a particular TCP connection in the kernel. The easiest way, I assume would be to use a printk or a printf and print out the corresponding variable which I assume is snd_cwnd in the kernel.
Is there a…
lordlabakdas
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how to find out which tcp congestion control my os is using
I would like to find out which congestion control algorithm my computer is using.
I know I can google it, but I want to find out by experimenting.
My first step was to run wireshark when I downloaded a big file.
Then I tried the IO Graph and got the…
obs
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TCP congestion window size in slow start phase
I have a question about the increasing rate of TCP sender's congestion window during the slow start phase.
Traditionally, the size of cwnd exponentially increases for every RTT. For instance, if the initial cwnd value is 1, it increases…
user1695882
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How can I retrieve current TCP congestion window size from the kernel? Any command or simple script?
Is there any command or script to retrieve the current TCP congestion window of a tcp connection. So suppose some communication is going on over tcp through the network interface (eg. eth0), now is there any way to dynamically (periodically)…
Slayer
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congestion avoidance on tcpgraph
I'm trying to understand congestion avoidance on a realistic tcpgraph. I already looked up graphs of congestion avoidance, but they don't really align with mine. I know that congestion avoidance happens when the line goes from exponential to linear.…
Noah H
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TCP slow start/congestion control behaviour query
I have a throughput issue on high latency (175ms) link and need help to understand why throughput growth transitions out of slow start. At first the server sends data in batches of 10 and throughput increases after each ACK but then transitions to a…
imac
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Why is the congestion window so large?
I'm a student who wants to experiment with congestion control with NS3!
I'm new to NS3, so I'm trying to experiment with open source on GitHub, but the results of my open source experiments seem a bit strange..
Below is the open source I found, but…
김민지
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Why is the sender server sending packets larger than the receiver's current window size?
i know that the receiver machine's window size can be calculated like this:
In the SYN package: (2 ^ wscale) * win. According to tcpdump output the initial window size is:
(2 ^ 7) * 64240
128 * 64240 = 8222720 Byte Window Size.
Please have a look at…
tonny
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How to solve the "R2 invalid mem access 'inv'" error when i try to loading the ebpf file named bpf_cubic.c
The linux kernel source code version is 5.11.0
I tried to load the congestion control algorithm which is implemented by eBPF.
The file is linux-source-5.11.0\tools\testing\selftests\bpf\progs\bpf_cubic.c.
I used the libbpf-bootstrap so I made some…
earle
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How to Reduce Congestion When Uploading Images to SharePoint
So I have created the following script:
class spImageUpload()
{
private static System.Collections.Generic.List keywords;
private static NetworkCredential credentials = new NetworkCredential(username, password, domain);
…
This 0ne Pr0grammer
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Can a client and server use different congestion algorithms when communicating?
I'm writing a http3 (which runs on quic) library, and there's a requirement of choosing different congestion control algorithm by caller. I did some Research and read this:
There are several variations and versions of the algorithm
implemented in…
psionic12
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Why cwnd doesn't increase immediately after a RTT when reno in congestion avoidance stage？
I use tcpdump to get packets of sender by downloading file from sender. The sender use Tcp reno.
But it seems that cwnd doesn't increase immediately after get enough acks.
See 2 pictures.
details in wireshark ,
tcptrace in wireshark.
The cwnd is…
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Why Linux(newer version) congestion control doesn't follow RFC5681?
I was just studying at TCP congestion control.
When I read chapter about slow start, I turned to RFC5681, I found that the standard showed that
If SMSS > 2190 bytes:IW = 2 * SMSS bytes and MUST NOT be more than 2 segments
If (SMSS > 1095 bytes) and…
LimingFang
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