LinuxQuestions.org
Visit Jeremy's Blog.
Home Forums Tutorials Articles Register
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Networking
User Name
Password
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.

Notices


Reply
  Search this Thread
Old 10-09-2009, 02:23 AM   #1
egarim
LQ Newbie
 
Registered: Oct 2008
Posts: 3

Rep: Reputation: 0
Linux QOS simple queue fifo doesn't work


Hi all, I begin to do some experiments with tc :
this is an example to shape my outgoing bandwith on eth0 to 128kB:

tcng output:

dev "eth0" {
egress {
fifo ( limit 128kB );
}
}


tc output:

tc qdisc add dev eth0 handle 1:0 root dsmark indices 1 default_index 0
tc qdisc add dev eth0 handle 2:0 parent 1:0 bfifo limit 131072

If I try to send data to another host in my lan the speed is alway 8-10 Mbyte/sec , I don't really known why... Did I wrong queue ? If I run tc -s I notice the packets flow that queue

tc -s qdisc show dev eth0
qdisc dsmark 1: root indices 0x0001 default_index 0x0000
Sent 72509672 bytes 8817 pkt (dropped 0, overlimits 0 requeues 0)
rate 0bit 0pps backlog 0b 0p requeues 0
qdisc bfifo 2: parent 1: limit 128Kb
Sent 72509672 bytes 8817 pkt (dropped 0, overlimits 0 requeues 0)
rate 0bit 0pps backlog 0b 0p requeues 0

Could anyone explain this to me ? Best regards.
 
Old 10-10-2009, 08:54 AM   #2
egarim
LQ Newbie
 
Registered: Oct 2008
Posts: 3

Original Poster
Rep: Reputation: 0
Unhappy

Quote:
Originally Posted by egarim View Post
Hi all, I begin to do some experiments with tc :
this is an example to shape my outgoing bandwith on eth0 to 128kB:

tcng output:

dev "eth0" {
egress {
fifo ( limit 128kB );
}
}


tc output:

tc qdisc add dev eth0 handle 1:0 root dsmark indices 1 default_index 0
tc qdisc add dev eth0 handle 2:0 parent 1:0 bfifo limit 131072

If I try to send data to another host in my lan the speed is alway 8-10 Mbyte/sec , I don't really known why... Did I wrong queue ? If I run tc -s I notice the packets flow that queue

tc -s qdisc show dev eth0
qdisc dsmark 1: root indices 0x0001 default_index 0x0000
Sent 72509672 bytes 8817 pkt (dropped 0, overlimits 0 requeues 0)
rate 0bit 0pps backlog 0b 0p requeues 0
qdisc bfifo 2: parent 1: limit 128Kb
Sent 72509672 bytes 8817 pkt (dropped 0, overlimits 0 requeues 0)
rate 0bit 0pps backlog 0b 0p requeues 0

Could anyone explain this to me ? Best regards.
I find :

***
14.1. bfifo/pfifo

These classless queues are even simpler than pfifo_fast in that they lack the internal bands - all traffic is really equal. They have one important benefit though, they have some statistics. So even if you don't need shaping or prioritizing, you can use this qdisc to determine the backlog on your interface.

pfifo has a length measured in packets, bfifo in bytes.
***

So the fifo is not useful to shape or better it CAN'T shapes! Correct me if I wrong maybe I misunderstood ?

Last edited by egarim; 10-10-2009 at 08:56 AM.
 
  


Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
Weird FIFO problem on Linux 2.6 darkwoods Programming 8 06-27-2010 03:40 AM
Is it possible for me to write in front of queue in case of message queue? hemanthv414 Linux - Newbie 1 11-17-2008 04:40 PM
How to interrupts work queue with signals iamjayanth Linux - Kernel 1 11-10-2008 04:39 AM
Linux 2.6 FIFO vs Linux 2.4 FIFO gjpc Programming 4 03-19-2008 07:26 PM
Simple QoS dunkyb Linux - Networking 1 05-11-2005 04:49 PM

LinuxQuestions.org > Forums > Linux Forums > Linux - Networking

All times are GMT -5. The time now is 12:38 PM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration