Welcome to the MacNN Forums.

badtz · May 17, 2004, 01:09 AM

I'm on DSL and when I upload at the absolute max, my download speed slows to a crawl.

Someone suggested that if I only use up 85-90% of my upload speed, my download will still reach it's maximum potential.

QUESTION :

Is there anyway to personally LIMIT your upload speed at a certain kbps? So I never max out my upload speed.

[if I send via FTP for example, it'll always want to use the maximum speed for uploading, anyway to limit that?]

dtriska · May 17, 2004, 03:18 AM

http://www.versiontracker.com/

badtz · May 17, 2004, 01:22 PM

Originally posted by dtriska:
http://www.versiontracker.com/

already searched for 'upload'. didn't find anything.

pat++ · May 17, 2004, 02:32 PM

look for carrafix on versiontracker.

badtz · May 17, 2004, 03:25 PM

does that block application specific speeds?

or can I block the upload speed for my whole connection?

[carrafix looks like it's only application specific?]

diamondsw · May 17, 2004, 05:01 PM

Just so you know...

Whenever you make a connection, whether that's to a web server to get a page, or to a P2P network to get a new file chunk, you have to perform what's called the TCP 3-way handshake. You send a request, get a response, and then send a response that you got the response. If you're uploading to the limit of your bandwidth, it gets difficult to send those handshake packets, and thus your download speed appears to suffer.

Unfortunately, general fixes are very difficult. Check out throttled, but be warned that configuration is quite difficult.

Phranken9 · May 17, 2004, 11:08 PM

Did you actually try out Carrafix?

It's not applications specific, it is port specific, so in your case you would throttle ports 20 and 21, the default ports for ftp.

To find out what ports the program you are using uses, check out this list at IANA. Commonly Used Ports

If your only use is for ftp, it might be possible within your ftp client, I know that the cli ftp program included with OSX has a throttling feature.

badtz · May 18, 2004, 05:18 AM

Oh!

I thought [from the Carrafix website] that it was application-specific.

Hmmm ..... does this program use a lot of memory [since I would assume it would always need to be on]

Also, can anyone recommend a size that I should cap off my upload speed at on a DSL line with 384-412 kbps maximum upstream?

thanks!

ginoledesma · May 18, 2004, 07:44 AM

The issue is system-wide (since all applications on your computer share the same networking resources). Some applications have the feature to throttle their bandwidth usage, so they behave properly. For example, iGetter and SpeedDownload let you specify the speed limit.

I'm not sure if the included ipfw tool in Mac OS X has bandwidth throttling. If it did, then I think it should be simple enough for someone to write an application to limit the speeds.

Some routers have the option of controlling the speed limit on a per-application (TCP port), per-client (IP Address), or per port (physical port). I'm not sure which routers support this, but I think some of the Linksys with customized firmware do. What's nice about router-side throttling is that it gives other clients on the network enough free bandwidth.

Phranken9 · May 18, 2004, 10:16 AM

Originally posted by ginoledesma:
The issue is system-wide (since all applications on your computer share the same networking resources). Some applications have the feature to throttle their bandwidth usage, so they behave properly. For example, iGetter and SpeedDownload let you specify the speed limit.

I'm not sure if the included ipfw tool in Mac OS X has bandwidth throttling. If it did, then I think it should be simple enough for someone to write an application to limit the speeds.

Some routers have the option of controlling the speed limit on a per-application (TCP port), per-client (IP Address), or per port (physical port). I'm not sure which routers support this, but I think some of the Linksys with customized firmware do. What's nice about router-side throttling is that it gives other clients on the network enough free bandwidth.

I think that the hardware you're thinking of are switches as opposed to routers, which usually run a bit pricier and much more customizable than the routers which most of us have in our homes. I don't have any experience with those, but I think that is much more than badtz really needs.

I believe Carrafix used 10-15% of CPU last time I used it, but there has since been an update or two which claim to drop usage. It also has various recommended settings depending on your connection, and if you find those don't cap it enough, they're totally customizable.

Go ahead and give it a download, see if it is right for you, it is donation-ware, and if it doesn't work for you, give throttled a shot.

[APi]TheMan · May 18, 2004, 11:03 AM

Originally posted by Phranken9:
I believe Carrafix used 10-15% of CPU last time I used it, but there has since been an update or two which claim to drop usage. It also has various recommended settings depending on your connection, and if you find those don't cap it enough, they're totally customizable.

Go ahead and give it a download, see if it is right for you, it is donation-ware, and if it doesn't work for you, give throttled a shot.

throttled uses less than 1% CPU and has options to prioritize ACK packets (part of the handshaking process that says, "Yeah, I got that, send the next one) and can leave packets destined for the LAN unthrottled.

Nice app, really.