Transmission causing slow internet access generally

[mikecad]

Hi there,

I'm experiencing some internet slow down problems which seem to be related to Transmission. We have a Macbook and a Macbook Pro downloading and seeding torrents. Both are configured with the same settings regarding number of peers to connect to, upload and download rates etc.

We have a 20mbit Virgin Media connection which I believe has an upload speed of 48kbytes per second. Both Mac laptops have been reduced to 6kbytes per second upload with unlimited download. Also each is allowed three active torrents at a time. All port forwarding rules are configured and each laptop is happy that inbound connections are working ok.

Once Transmission has started downloading torrents the ping response times to external destinations (e.g. google.com or co.uk) increase from around 30ms to over 11000ms. Web browsing is unresponsive taking minutes to load a single page. Also it seems to impact my LAN wireless speeds (I have a time capsule running 802.11n) and transfers slow significantly when this is happening. Closing Transmission on the Mac's returns the ping response times back to 30ms. I've tried disabling PEX as has been mentioned on another thread but the problem persists.

I spotted on another thread that they reduced their upload limit to 1kbyte per second. I changed both Mac's to 2kbytes per second each upload and all of a sudden the ping times went back down to 30ms. All now seems much better but I'm concerned now that there is a problem possibly with Transmission and I'm not able to seed properly, especially for sites requiring upload/download ratio.

Any thoughts?

Mike...

[tallearthling]

Have you enabled throttling in Transmission? I would suggest setting it for no more than half of the bandwidth you supposedly get from your ISP.

Have you tried limiting the number of peers in Transmission? I believe the default is 200. My connection, though fast, doesn't like 200 peers connected all at the same time. I slowly dropped mine in increments of 10 until I got a good balance at 160.

[essiw]

if your upload limit goes higher then your upload bandwitdth it blocks your download bandwidth

[Yada]

As you've limited your upload speed that should not be the problem. You say you're not limiting the download speed however. I would suggest trying that, seeing as you are using a Time Capsule as well.

[mikecad]

Hi All,

Thanks for the responses so far. I've been running Transmission with the upload capped to 2kbytes/sec since my last post and so far I've not had any issues with internet performance. What I am experiencing is slow LAN over wifi.

I use my Time Capsule as a NAS (I don't actually use it with Time Machine). I have music, videos as well as software housed there. I've spent hours trying to figure out why I am getting slow reads and much quicker writes to the Time Capsule.

Again I've been able to attribute this to Transmission. When Transmission is running (currently I'm set up to 120 maximum connections with 50 for new transfers and am downloading two torrents and seeding three completed torrents), my read speed from the Time Capsule is around 200kbytes per second. This is on an 802.11n network. The write speed is around 4 megabytes per second. Because it is one of the new Time Capsules I have both 802.11g and 802.11n networks running simultaneously and the poor read performance is evident on whichever one I connect to.

My test file was a 2+GB Jam Pack which I copied from the Time Capsule over wifi to my Mac. With Transmission running the ETA was over 5 hours. When I stopped Transmission the ETA was 9 minutes. I left the longer job running for a couple of hours to make sure Finder was giving a relatively accurate figure.

Someone mentioned capping my download limit, my current torrents have been using no more than 200kbytes per second (not too many good seeders). I'll try capping it, but you said that "seeing as you are using a Time Capsule". Are they notorious for this kind of thing re torrents? I'm half tempted to move back to an earlier version of Transmission to see if the problem persists. Any more comments would be more than welcome as it is driving me mad. Also worth noting is that when my Transmission is running, my girlfriends Mac has no problems reading files from the Time Capsule at high data rates. So the Time Capsule seemingly isnt being monopolised resources wise, and is only slow to a connected IP which is torrenting.

Thanks again.

[mikecad]

I've been doing some more investigation and it is not Transmission causing the problem. My wifi LAN slow down on my Macbook Pro occurs when I'm downloading a file. I go from a read rate of 5 megabytes per second to a few hundred kilobytes per second, even though the download via Safari is showing only 200 kilobytes per second.

It is almost like the Time Capsule favours internet traffic over internal LAN traffic to the Time Capsule disk? To test this theory I have a TVIX 6500 media player hooked up to the Time Capsule via gigabit ethernet. Whilst I am downloading a large file from the internet, my large file transfer from my Time Capsule to my Mac is taking up around 200 kilobytes per second (according to activity monitor), simultaneously I am downloading an AVI from the TVIX. Hey presto the TVIX takes the incoming network traffic up to about 5 megabytes per second.

So it is some issue with the Time Capsule serving data from the internal disk and priorities? I'm going to move over to a Time Capsule forum for this one, apologies to the developers of Transmission for my assumptions that it might be a Transmission related problem

Thanks All.

[SinisterDexter]

I'm tempted to disregard your theories regarding your Time Capsule as I experience exactly the same issues with Transmission and slow internet activity, but have no Time Capsule.

Here's my setup:

US Robotics USR8054 wifi router connected to Virgin Media 10Mbit (1MB down, 64k up stream) via cable modem

G4 PowerMac, wired, serving iTunes via Firefly to a Roku Soundbridge, and Connect360 serving media to an Xbox 360 - occasional Transmission use

MacBook Pro, wireless, serving via Firefly and Connect360, occasional Transmission use

Roku Soundbridge, served audio and direct internet radio

Xbox 360, served media and Xbox live


So, there's up to 4 devices sharing one 10Mbit connection but everything hangs together pretty well, until I run Transmission...

If I run Transmission on either Mac I usually experience internet slow down, although not always immediately. I've limited my number of connections and both downloads and uploads are throttled to avoid swamping my cable connection. The slowdown doesn't appear to be bandwidth related anyway as I will still have slow internet speeds even if, for example, Transmission is downloading at 10k and uploading at 0k. This should have almost no impact on internet activity and yet it kills my connection speed. Local network activity functions as normal with no noticeable drops in speed at any point, but my internet connection drops to dial-up rates, slower at times.

Every time I shut Transmission down internet activity returns to normal, implying there is something amiss with Transmission - or it's possibly the result of some sort of IP filtering or traffic-shaping on the Virgin Media network. The only other link in the chain is my router, but that can be ruled out as I replaced it a while back with a Zoom router, only to find exactly the same result - now I'm back with the USR.

I've not really found a reliable solution to this other than make sure I don't need to do anything else while Transmission is running - and pray for a quick download

Are there any other Virgin Media users out there with the same problem?

Cheers, Dex

[trampjuice]

Yep. Limit the upload and download speed. Its the upload speed option unlimited, that creates havok on a connection, it should be set to 40kb max on 10mbit. Do a speedtest with speedtest.net or whatever its called, before and after you sort the upload speed. The 0Kb up and 1.2Kb down that transmission reports doesnt mean that its not using up all your bandwidth to try and send packets, just that successful packets are not getting thorugh because of the latency issues unlimited option causes. For example a ping will not come back for seconds, when it should be 40ms.

[curious297]

Machine: 2Ghz Mac Mini, Leopard, 20GB Free Disk space, 4GB Ram.
1 x 8 port Gigabit Switch
Torrent Client: Transmission V1.91
Torrents: Downloading to an external 2.5" usb Drive
Internet: 10Mb up / 1 MB down
Ports: Open and working. Checked from http://www.canyouseeme.org/
Global Maximum connections / Maximum connections: 300 / 50
ISP: Confirmed they are not throttling or playing with my traffic.

I came across this thread after seeing some crazy ping times on my Gigabit network causing slowdown of downloading internet pages, accessing my other servers on the network and generally having a hard time to do anything internet related whilst downloading torrents using Transmission. I cannot watch a movie streamed from my movie server (Gig network) to my Mac, both music and movies stutter and at worse, I cannot get a directory listing from my server as it times out!

Having read all available information about other people having the same problem, I started to investigate why this was happening.

So here's a quick explanation of my problem. I'm not sure when it started but since I have been using Transmission from about V1.6+ I have had these long ping times. I checked my available memory and like others, I could see that I was down to about 20-30Mb of free ram. This was my initial suspect so I went out and upgraded my Mac mini to 4GB of ram. Did this make a difference? No!!! I know have over 1 Gig of free Ram and I still get ping times ranging from 190.00 going up to 999.000 and Higher!!! I'm pinging my server which is on my internal network so ping times should be minimal.

I have tried everything from adjusting the UL/DL ratios, reconfiguring the modem, etc etc. The strange thing is:

1. My upload speed is always at it's maximum whenever possible.
2. I get full speed of any torrent with more than 2,000 seeders.
3. Any torrent with less than 2,000 seeders, I am lucky if I get more than 20KBs
4. I can connect to over 50+ seeders / Leechers and still get very very low DL speeds.
5. Even if I download 1 torrent , ping times go haywire.

What I have noticed is that the ping times increase when Transmission has peers connection and disconnecting. If a torrent reaches it's maximum connection, the ping times seem to return to normal.

Also find that my DL speed is very erratic going from say 10KBs directly to 300KBs then back down to 20KBs then dropping to Zero.

Like others have witnessed, once I turn Transmission off, all network activity returns to normal.

Has anyone found a solution to this problem as I don't want to have to change to another client.

[Jakobud]

This is an old thread but it sounds like it wasn't resolved.

In a typical home network, your major slowdown from BitTorrent clients (any client, not just Transmission) can easily occur when a single torrent is connecting to too many peers. It doesn't matter how fast its transmitting data back and forth between the peers. They could be downloading/uploading at something slow like 1k/sec but still its going to slow down your overall network even though you haven't come close to maxing out your bandwidth. It really doesn't have anything to do with bandwidth. Just connections.

So within Transmission, the easy fix is to limit the number of connections per torrent to something lower. You can easily try this out right now and see if it works just by limiting it to 1 or 2 peers instead of 60 or whatever the default is. With Bittorrent clients for me, I've found that more than 10 peers is unnecessary and 10 fixes network speed issues for me. Your mileage may vary.

Btw, this goes for all bittorrent clients. I used to use uTorrent and I had the same network slowdown issues until I limited the number of peers per torrent.