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Traffic shaping might sound fancy. And it can be, but here is a trick I use to improve performance on my LAN at home.
Here is the problem: If one of my computers is uploading large files, it makes surfing the web really slow on all my other computers.
One of my computers periodically uploads large backups to the net. Since I only get 40kbps up, sending 300Mb files can take a while. During the upload, all other outbound traffic has to get inline with the packets getting sent for the backup. This basically makes surfing the web nearly impossible. Surfing the web usually uses very little of the out bound bandwidth.. but if one of my boxes is trying to consume all of the outbound traffic, life sucks.
What I did to fix this problem is throttle the outboud traffic coming out of my uploader box. If the upload is using 90% of my outbound band width that’s fine, my http requests can fit in there comfortably.

here is the command I used for doing that

sudo tc qdisc add dev eth0 root tbf rate 400kbit latency 50ms burst 1540

you should play with the 400kbit part to get it tuned if you want. Too low and your upload will take forever, too high and your surfing will suck.

To delete the filter:

sudo tc qdisc del dev eth0 root tbf

I figured out how to do this while working on The Digital Tipping Point when we were uploading abunch of video to the Internet Archive.

Posted on Monday, June 9th, 2008 at 6:07 pm in bash, code, DTP, web | rss feed for comments| Responses are currently closed, but you can trackback from your own site.