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Firefox does not utilize all available bandwidth for downloads

  • 3 replies
  • 1 has this problem
  • 1 view
  • Last reply by chblock

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OS: Windows 7, FF Ver: 60.0.1

Hello,

I have a 100Mbit internet connection that reliably speed tests +100Mbit. When I do a download through Firefox on Win7 the best I can get is about 25Mb. All of my other Win7 download clients including Free Download Manager and uTorrent max out my bandwidth.

On my FreeBSD system Firefox does NOT exhibit this problem. It rules out the possibility of poor connection speed over a single connection to a particular server. There's a couple fast ones close to me where I can reliably max out my bandwidth. I'll try a download on the FreeBSD system using FF then get a quarter the speed when I try the same download immediately afterwards through FF on the Windows system.

I've tried a lot of things thinking it might be something with the way my Win7 machines are set up or a problem with a driver. I've gone to the latest video drivers and ethernet drivers with no change. I tried a fresh Win7 install and that didn't make any difference. I have several Win7 machines that exhibit this problem. I don't know if it's any help, but Chrome also exhibits this problem.

If downloads are not running at full speed then it stands to reason the browser is not utilizing all available bandwidth to run at maximal speed. I'm concerned my browser is limited to operating at 25Mb. That would be a drag since I'm paying for a 100Mb connection. I can use FDM to handle downloads and get full download speed, but I'd rather not have to do that and I'd rather rest assured my browser is using all available bandwidth.

Thank you,

 - Craig
OS: Windows 7, FF Ver: 60.0.1 Hello, I have a 100Mbit internet connection that reliably speed tests +100Mbit. When I do a download through Firefox on Win7 the best I can get is about 25Mb. All of my other Win7 download clients including Free Download Manager and uTorrent max out my bandwidth. On my FreeBSD system Firefox does NOT exhibit this problem. It rules out the possibility of poor connection speed over a single connection to a particular server. There's a couple fast ones close to me where I can reliably max out my bandwidth. I'll try a download on the FreeBSD system using FF then get a quarter the speed when I try the same download immediately afterwards through FF on the Windows system. I've tried a lot of things thinking it might be something with the way my Win7 machines are set up or a problem with a driver. I've gone to the latest video drivers and ethernet drivers with no change. I tried a fresh Win7 install and that didn't make any difference. I have several Win7 machines that exhibit this problem. I don't know if it's any help, but Chrome also exhibits this problem. If downloads are not running at full speed then it stands to reason the browser is not utilizing all available bandwidth to run at maximal speed. I'm concerned my browser is limited to operating at 25Mb. That would be a drag since I'm paying for a 100Mb connection. I can use FDM to handle downloads and get full download speed, but I'd rather not have to do that and I'd rather rest assured my browser is using all available bandwidth. Thank you, - Craig

Modified by chblock

Chosen solution

I got lucky with some internet searching and found out what's happening. This article describes it nicely.

https://www.duckware.com/blog/how-windows-is-killing-internet-download-speeds/index.html

Basically Windows default TCP configuration can limit bandwidth utilization. Using this info I've solved my problem.

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You do realize that these are 3 different things. Firefox Download Manager, vs a a Add-on that is made specifically for boosting speed and Torrents which share data between 2 - 100thousand (example) people running a client specifically for that. You can not compare apples to oranges to a banana

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I do understand the difference in connection with a peer to peer client like Bittorrent and an accelerator like FDM. I'd have been better served to leave that out since I see the download speed question explained continually to people that don't understand the difference.

I'm not comparing apples to oranges, I'm comparing Firefox on FreeBSD to Firefox on Windows 7. They're using the same everything except the operating system. One is four times faster than the other. That being the case I'm quite sure there is a problem. Granted it could be the difference between Windows and FreeBSD, one sucks, the other rocks, but I'm trying to find out if there's anything I can do about it.

Modified by chblock

more options

Chosen Solution

I got lucky with some internet searching and found out what's happening. This article describes it nicely.

https://www.duckware.com/blog/how-windows-is-killing-internet-download-speeds/index.html

Basically Windows default TCP configuration can limit bandwidth utilization. Using this info I've solved my problem.