Jump to content

Constant short freezes/lag


Recommended Posts

When I'm dling using utorrent, my comp will experience freezes/lag for like half a sec every minute or so..but if the is no dl activity on utorrent this does not happen. I'm using utorrent 1.8. I dont understand why. I wont notice it unless I'm watching a movie or playing games. Can tell me how to fix this..

Link to comment
Share on other sites

Run Speed Tests on your connection, it is EXTREMELY important to know your connection's measured upload speed max for purposes of choosing uTorrent's settings.

2nd link in my signature is suggested settings for uTorrent based on your upload max.

You'll probably need to disable:

DHT, Local Peer Discovery, UPnP, and Resolve IPs

Peer Exchange reuses peer and seed connections, so you can leave it enabled.

Then try testing with uTorrent's half open rate as low as 1.

I'd be shocked if you have problems after that...

Link to comment
Share on other sites

hey there..thanks for your help..i think the 'Local peer discovery' is causing the trouble.

i normally have DHT, UPnP and Resolve IPs off. The other settings doesnt seem to have caused the problem. =)

I guess local peer discovery is useless unless there are people sharing on the network.

Link to comment
Share on other sites


1. My solution.

Setting half open connections to 1 solved the problem completely here. Nothing else did.

For that, go to: Options > Preferences. Click 'Advanced' in the left row.

In the right pane, click on: net.max_halfopen.

Under 'Value': change from 8 (default) to 1. (so Value = 1)

Click SET. (Very important! If you just click OK, the setting will NOT be changed!)

Click OK to leave the Prefs-window..

If this did solve the problem, you may try higher values of the Half Open Connection. The max value doing well here is 3.

Switeck, MANY thanks for that tip, then the problems were huge here.. :-)

2. Checking the problem.

The most simple (but rather bad) way to check if the problem persists, or has been solved, is this:

Press Ctrl+Alt+Del to start Windows Task Manager. Click Tab 'Processes'.

Click CPU. Wait a second, and Click CPU again. (this sorts the list by CPU use)

Click on uTorrent, just because selecting it, makes it easy to keep watching it..

Make sure uTorrent is downloading or uploading a lot.

Watch for a few minutes. If uTorrent continuously uses CPU (like 4% or something) the problem is gone. But if it often uses 0%, there may be trouble.

But this method is very inaccurate! Better do this simple thing:

3. Download Process Explorer.

Get "Process Explorer" to get a nice graphical moving performance overview of the CPU-use and Bytes I/O of uTorrent.

Without such a program it is hard to see the problem, or to see if it is really fixed.

It is a small free Microsoft download, very easy to use, and doesn't need to be installed:


Download at the bottom of the page, unzip it, and run it.

(Microsoft imported sysinternals-technology, so don't worry you get anything 'funny'.)

Run it. Double click uTorrent. Click Tab 'Performance Graph'. And stretch it a bit. Thats all.

It displays a 10 minute history of uTorrent's CPU and Bytes I/O history.

Freezes are best seen by watching Bytes I/O, then CPU-usage is too low to see it properly (4% average). But both are zero during freezing.

4. Does this problem corrupt uploading or downloading files?

I think not. I can't check if uploads are corrupted, but downloads are not. I collect documentaries and movies, often 1 GB large, and I never had corrupt files. So I assume, uploads are not a problem too, certainly now the receiving PC checks what it gets..

So if uTorrent only freezes for a second a minute, the problem is not very severe.

5. What was my problem?

Every minute or so, uTorrent freezed for 5 seconds or so. But Process Explorer showed variations in time intervals and freezing periods. Intervals could be from 15 seconds to 4 minutes, and freezes could be from a second to even 20 seconds. So sometimes even every 10 seconds I had a freeze of 7 seconds or so..

It did not freeze the PC completely during these seconds. Movies kept on playing, and eMule kept on down/uploading. But I am not completely sure if it didn't affect IE and Mail: they can be very slow at times, but the cause may be different.

I permanently upload about 800 KB/s, and download nothing. (fibre connection: 10 Mbit/s download, and also 10 Mbit/s upload).

PC = Athlon 3000, 2 GB memory, probably clean (smart use of Ghost-Images).

I don't know at what uTorrent version the problem started. Maybe 1.6 or 1.7. Currently I run 1.8.

6. What did NOT solve the problem?

- Stopping eMule did not solve the problem.

- It was not the Firewall. Even completely uninstalling the firewall (Outpost) didn't solve the problem. (I've got Windows Firewall off.)

- I suspected the settings. So I completely uninstalled and reinstalled, getting a fresh default settings.dat. It didn't work.

- I suspected Resume.dat. The list of uploads could be corrupt. So I started with a clean Resume.dat, adding all torrents again. Zero result..

- I suspected the ISP to cut off speed during short periods, and uTorrent not being able to handle that. But since the HalfOpen setting solved the problem, this is not the case.

7. Changes of settings, that did NOT give results.

Switeck mentioned some settings. I experimented with some more:

Options > Preferences > Connection > Enable UPnP port mapping.

Options > Preferences > Connection > Enable NAT-PMP port mapping.

Options > Preferences > Bittorrent > Enable DHT network.

Options > Preferences > Bittorrent > Enable DHT for new torrents.

Options > Preferences > Bittorrent > Enable Local Peer Discovery.

Options > Preferences > Bittorrent > Ask tracker for scrape information.

Options > Preferences > Bittorrent > Enable Peer Exchange.

This took me some hours, and was very confusing. I got very different results. (that is logical: the problem was something else.) Sometimes with everything off, it worked perfectly, but a few hours later is was a mess again. Sometimes it was perfect, but even clicking on anything in uTorrent caused immediate freezing, getting the whole problem back.

I tried two good methods. First have everything On, and step-by switch things off, and see if it gets better. Or the other way around: Everything Off, and slowly switching things on to see when the problems begin. But it all resulted in nothing. And I forgot to click SET at the new HalfOpen-setting, so I kept the wrong default value of 8.

8. Switeck Thanks! :-)

A small political note. (that's risky, then you may not like it..) I care about uploading. I collect all documentaries and movies about the Israeli-Palestine issue. Made by Europeans, Americans, Arabs and Israeli's. All of very good quality. But the thing is: If you look at those, and read a few books to, they ALL point at ONE direction. There is no escape from that: the whole matter is caused by our western policies, and the problems persists due to our policies. Things like Hamas violence in fact have a very minor role in all that. The whole issue is one big log of our western violations of the basic UN rules for peace between nations. These rules determine what is objective or not. And in this case there is no such thing as an objective view above parties. In fact it is the biggest scandal in our international politics for tenths of years now. I've seen all objections against this view failing for many years now. It's not a matter of politics, but merely of organised crime (according to our own rules about that).

So that's why I want my uTorrent work well. I feel obliged to spread all this quality info, and share only these..

I do not want to make political statements here, but in case of Israel our countries continuously help to violate Land Rights, Human Rights, and international laws about war, replacing them by the old laws of power and wild-west again. I do not want to offend anybody, but I find this must be mentioned much more often in any place, just to get things changed. We're supposed to be the civilised world, but tend to wander off.. Thanks for reading and helping..

Link to comment
Share on other sites

What uTorrent settings are you using now?

Symmetric 10 megabits/second connections are still pretty rare where I am at, in the USA.

I gave up on national and most international news agencies being anywhere near unbiased years ago. The latest debates on ComCast really are proof of that. Read an article on the Wall Street Journal (WSJ) today that was just plain lies about what ComCast is doing that have since been refuted multiple times. Almost makes me wonder if the reporting journalist's paycheck is paid by WSJ or ComCast. :P Admittedly, I'm unaware of ComCast killing anyone over this...unlike your subject...but it's still a worthy example of news media favoring big business every chance they get.

Link to comment
Share on other sites

Good day, Switeck!

I do not use special settings. I just install uTorrent, and I think I specify bandwith. That's all. So all the settings you mentionned, I have on, or checked..

The only change I made now was the number of HalfOpen connections, set to 3 here. Works perfectly. Maybe a small gap every half hour..

I was lucky to get such a huge bandwith. Only a few cities in the Netherlands have a complete new Fibre network, even in their poor areas. They say Fibre always comes symmetric. Here it is. So for 50 dollar a month or so, I have this, and cable TV and even telephone. uTorrent still uses only 4% or so during uploading 10 mbits/s.

Tired of biassed media? I can imagine.. The Dutch think they have better news media and debates,but seeing everything about the Middle East and terrorism, they may be even worse. I never believed it could be that bad.

Googling on ComCast immediatately gave Dutch news (so they do something good) pointing at the Wall Street journal. I read it, and immediately saw how the FCC was accused of "playing cop". Did the WSJ use those words too, after the government made al these laws since 911 that are a severe intrusion in private life? I think not.

And what the article in fact does say, but does not pay attention to, is that many consumers may have bought a fast connection especially for video exchange. So they were cheated already. Fine moment for the WSJ to protest against someone playing cop against that. Part of business ethics according to the WSJ?

Link to comment
Share on other sites

"Pro-Business" means not having to talk about ethics. Your core audience wouldn't understand if you did anyway.

<- on ComCast...seeing crazy disruption/crippling of BitTorrent traffic that's basically unavoidable and with unknown triggers.

The 10 megabits/second upload setting in the 2nd link in my signature may work better than what you have...but if you're lowering the upload speed well below the amount it recommends, just use the 5 megabits/second upload setting and raise upload speed instead. :P

Link to comment
Share on other sites

1. Business ethics? Let's leave it, before we fill 20 pages about that, merely drama.. I suggest the world should have an annual 'Business Weeping Day" or something..

2. About the chart in your second link..

You probably use Firefox or Opera! :-) In Internet Explorer 7 the layout is pretty messed up. It is much too broad, so every line becomes 1 1/2 line, making it hard to recognise what the numbers stand for. I pasted it in a Word document, and only then I saw the nice original as it should be.

The reason to paste in Word was, it looked soo bad, I didn't believe you intentionaly would leave it like that.

So, since most of the readers will use IE, most of them will get a messed up table.

Perhaps ask the organisation here, if anything can be done about it.. (update the forum software FluxBB?)

3. About settings:

I take your advice, and choose the settings for 5 mbit/settings, then raising speed. I've read your article, and found out where the settings can be adjusted, but I leave it for now.. It took me an hour, and at the moment everything is too busy and demanding.. But thanks for now! :-)

Link to comment
Share on other sites

My last posts in my speed guide message thread was intentionally long to explain the reasoning for my suggested choices. Some of them are just reusing what uTorrent's normal Speed Guide (CTRL+G) spits out, for familiarity and to avoid having to argue with someone over it. The rest I tried hard to meet conflicting goals.

Even still, some of the values are a little in doubt -- especially in light of what I've recently read about hostile ISPs (how Sandvine works) and really bad networking hardware and software.

I'm aware the chart's messed up on IE.

Quite frankly, I've reposted the chart more than 5 times and nothing seems to work.

I'm not sure IE even supports a fixed-size font. :(

Link to comment
Share on other sites

Thanks! I write long articles myself, and know the risk of people leaving it, if it is a bit too complicated, or not completely clear what the use or the conclusions are. Another point is, for many English is not their native language, and reading costs time. And I find it easier to read English, written by those that are not used to it. That eliminates misunderstandings about expressions, that may be common to the English speaking, but not to others. (but I'll take a good look at your work next week)

Anyway, I really appreciate what you do. And uTorrent works great. Really well done, such a small program, being highly efficient in many ways. Thanks for the good support here.

Would the designers read here about the problems with too many half open connections?

Should default values be fixed in a next version? Should I mail them or so?

Link to comment
Share on other sites

I've heard mixed reports that Vista home edition has a lower half open connection max than Vista Pro or any version of Windows XP. Since I don't have Vista, I cannot confirm...and have no plans to get Vista.

I am unsure of the interest levels of uTorrent's makers in changing the default values uTorrent has, both when you first run it...or Speed Guide values.

As such, I do not know if it's a good idea to email them...or even who exactly to email.

Link to comment
Share on other sites


This topic is now archived and is closed to further replies.

  • Create New...