I'm looking at ktorrent advanced preferences. What does fast cpu / slow cpu slider do? Can't find any info about it.

kriko wrote:I'm looking at ktorrent advanced preferences. What does fast cpu / slow cpu slider do? Can't find any info about it.

It's just there in case you are experiencing high CPU usage when you are using download or upload limits.

Hm, I got a bit of cpu burst, but only when I really pump up max connections values, so I suppose it is normal. But what does that actually? Controls niceness of ktorrent process? If I have fast cpu, turning this to slow cpu side, would spare some cpu cycles?

kriko wrote:Hm, I got a bit of cpu burst, but only when I really pump up max connections values, so I suppose it is normal. But what does that actually? Controls niceness of ktorrent process? If I have fast cpu, turning this to slow cpu side, would spare some cpu cycles?

No it's internal stuff, it controls the time to sleep in the networking threads when you have speed limits. Without the sleep time you would get very high CPU usage, without actually anything being done.

But this can result in you not getting the full speed you want, if you for example have 10 MB/s downstream and you set the limit to 5 MB/s, you might not get that 5 MB/s even though without the limit you would easily get this.

This can really only happen at high speeds like this.
99 % of the people do not have this bandwith available to them. You might however run into it on a LAN.

The networking threads poll all network connections (they tell the OS to wake them up when a connection has data ready). When you set a limit, you will not read all data, so if you immediately poll again, the OS will wake you up that data is ready, but because only a short amount of time has elapsed, you won't read much, and if you then sleep again, you will be immediatly woken again, to read a little bit more. And this keeps going on and on.

This results in high CPU usage, without actually doing much. So in this case we sleep some time, and then read a big chunk of data (as much as we are allowed by the limit), which is a lot less CPU intensive.

You apparently typed in KB instead of MB, George.

Thanks for such fully explanation. I guess it is best to leave it in the middle

lucke wrote:You apparently typed in KB instead of MB, George.

Not anymore