Lowering x264 priority

[asarian]

Is it safe to lower x264 priority (Windows Vista), with the Task Manager, to give some room for other processes too, CPU-wise? Or would it become unstable and abort? My current job has already been running for 48+ hours (with another 40 or so ahead); and I kinda need to do something mildly CPU-intensive inbetween. I'd hate for the process to collapse, though. So, has anyone ever successfully tried this?

Thanks.

[LoRd_MuldeR]

Is it safe to lower x264 priority (Windows Vista), with the Task Manager, to give some room for other processes too, CPU-wise? Or would it become unstable and abort? My current job has already been running for 48+ hours (with another 40 or so ahead); and I kinda need to do something mildly CPU-intensive inbetween. I'd hate for the process to collapse, though. So, has anyone ever successfully tried this?

Thanks.

Lowering the priority of a process (or even suspending it) will never effect its stability. So yes, it's perfectly safe ;)

Anyway, you don't need to lower the priority of x264 to get "room" for other processes. The scheduler of the OS will make sure that all processes get CPU time to run.

If all processes have the same (i.e. "normal") priority, the CPU time will be distributed among all processes in a "fair" way.

As soon as you lower the priority of x264 the other processes will be preferred over x264. That's it.

(EDIT: Actually setting the priority of a very CPU-intensive process to "real time" might result in the system stop responding. So better don't do that ^^)

[asarian]

Lowering the priority never effects stability. So yes, it's perfectly safe ;)
Okay, LoRd_MuldeR, thanks for your swift and decisive reply. :)

[asarian]

(EDIT: Actually setting the priority of a very CPU-intensive process to "real time" might result in the system stop responding. So better don't do that ^^)
Yeah. And if it won't stop responding, you might actually ere hurt your process, because I/O will become problematic (yes, tried that before, LOL; wasn't a good idea).

Kinda makes you wonder, though, whether setting it to 'Above Normal' or 'High' even, for during the night and such, would be a good idea. My experience on FreeBSD, at least, is that giving a process a higher priority is almost never a good idea, and rarely has the intended effect. But it might be different on Windoze.

At least it's a good thing I know I can safely lower the priority of the x264 process. :)

Thanks again, Lord Mulder

[Warperus]

But it might be different on Windoze.
It won't be good idea in Windows unless you have many processor-intensive operations you want to postpone. I hardly believe there is anything except trojan-downloaded distributed DNA research that can you want to avoid this way.

One more thing. Even though you reduce x264 priority to bewlo-normal your system responsibility will be lower than in case of idle machine. As x264 does not give up time quants unless disk I/O operations are too slow for encoding, it will use time quants given to it up to the end, so "additional" 10 ms delay for message processing of other application is nearly garanteed. It's generally not visible unless you use badly designed application, but sometimes it might be critical.
Well, running x264 on real-time critical computer is a bad idea. Video capture and similar tasks a better be done on computer without hordes of hungry x264 threads.

[LoRd_MuldeR]

Kinda makes you wonder, though, whether setting it to 'Above Normal' or 'High' even, for during the night and such, would be a good idea. My experience on FreeBSD, at least, is that giving a process a higher priority is almost never a good idea, and rarely has the intended effect. But it might be different on Windoze.

Well, raising the priority of x264 to "Above Normal" or even "High" won't make it encode any faster in a normal situation. Only if you had various CPU intensive processes running concurrently, it would help x264 to encode faster - and make those other processes "slower" at the same time. This may or may not be desirable. Also with x264 running on "High" priority other processes that don't need a lot of CPU time but require fast response on user interaction (e.g. a web-browser) might be effected. But that doesn't matter "over night", because there (usually) won't be any user interaction...