Opened 9 years ago

Closed 9 years ago

Last modified 8 years ago

#3641 closed defect (worksforme)

TOR high CPU then crashes

Reported by: YorkshireJumbo Owned by:
Priority: Medium Milestone: Tor: 0.2.2.x-final
Component: Core Tor/Tor Version: Tor:
Severity: Keywords: tor-client
Cc: torproject@… Actual Points:
Parent ID: Points:
Reviewer: Sponsor:


I've been using the Vidalia bundle for a while, changing to Polipo about 18 months ago. I use TOR to anonymize the connection to torrent trackers - not for the peer-to-peer connections! I seldom use Torbutton on FF, and it's been turned of for several days in case that was the problem.

The bundle started misbehaving a couple of weeks ago. I started getting lots of warnings about DNS resolution using Socks5, so I upgraded to the latest Vidalia bundle.

Now Tor starts out normally, but after anything from a few minutes to several hours the process starts hogging a CPU (>90%) and crashes after a few hours. Restarting it repeats the behaviour. I am still getting the DNS resolutiuon errors. The only application routing via Tor is uTorrent - I have been using an old build (v1.6) of this for many months without problem, so I am unsure what may have triggered the change

Child Tickets

Change History (9)

comment:1 Changed 9 years ago by YorkshireJumbo

Cc: torproject@… added
Component: - Select a componentTor Client
Milestone: Tor: 0.2.2.x-final
Version: Tor:

comment:2 Changed 9 years ago by Sebastian

Resolution: invalid
Status: newclosed is ancient. Also, please don't use bittorrent over tor.

comment:3 Changed 9 years ago by YorkshireJumbo

Resolution: invalid
Status: closedreopened
Version: Tor:

Surprised it's an old version, as I downloaded the Vidalia bundle off the site just before posting in an attempt to fix this. Anyway, I've now downloaded the latest version of TOR and installed that on top of the old version. Problem is, I still have the high CPU (uses 100% of a single processor most of the time).

Interestingly, when I closed most applications while on holiday, there was no such problem: Tor.exe ran as usual. Typically, I have Outlook 2010 and iTunes running most of the time along with other programs occasionaly, but I closed them for a few days, and Tor (the old version) ran fine. As soon as I started using the PC, the high CPU usage reappeared.

Could you explain why using TOR for torrent tracking is frowned upon, as it uses minimal bandwidth? I can see why I shouldn't download files over the network, and I don't because that is very difficult to track. However, the tracker sends out tiny requests every few minutes, so should have no effect on the network.

comment:4 Changed 9 years ago by silver

Resolution: fixed
Status: reopenedclosed

comment:5 Changed 9 years ago by YorkshireJumbo

Resolution: fixed
Status: closedreopened

OK - turned off using it for torrent tracking (and left it off for anything else torrent-related) after reading the blog - thanks.

Now used solely for the TORbutton on Firefox, so it's only used intermittently now. Started Vidalia and used TOR to browse for a short while last night. This morning, TOR was back to hogging a CPU at 90-100%, despite having no intentional traffic during the night.

Now I could solve this by stopping and starting TOR each time I need to use it for TORbutton, but the CPU hogging has only started recently and I'd rather have it run seamlessly...

comment:6 Changed 9 years ago by arma

How odd. Does the Tor Browser Bundle do the same thing for you?

Is your CPU slow? Try not to leave too many Vidalia windows open, especially the bandwidth graph and the network map window. Also, be sure not to configure Vidalia to log at debug level.

Also, are you *sure* you don't have applications running in the background that you forgot about that are configured to send their traffic through Tor?

comment:7 Changed 9 years ago by YorkshireJumbo

Resolution: worksforme
Status: reopenedclosed

I'm afraid I've had to turn Tor off now and only start it when I need it - it was getting too painful. I can't see what triggered it, as it seemed to happen at different times of the day. I had nothing open except the icon in the tray, and could use it fine for a while, then the CPU would soar while I wasn't using it. Logging wasn't at debug (notice stdout) and I only had 2 (uTorrent and FF), now 1, application set to use it.

I'm assuming that there is some service or application that "interferes" with how Tor works and triggers some activity. Now that I use it less frequently, I can work around the problem, so it's much less of an issue...

comment:8 Changed 8 years ago by nickm

Keywords: tor-client added

comment:9 Changed 8 years ago by nickm

Component: Tor ClientTor
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