x265 Limit threads

HandBrake for Windows support
Forum rules
An Activity Log is required for support requests. Please read How-to get an activity log? for details on how and why this should be provided.
Post Reply
delicious_storage
Posts: 5
Joined: Sat Jan 04, 2020 5:27 pm

x265 Limit threads

Post by delicious_storage »

Is there any way to limit the number of threads handbrake uses when encoding with x265? Lets say for example you had an 8 core CPU and wanted to encode and game at the same time, with x264 you could set threads=4 in the advanced options. Is there an equivalent of this for x265?
mduell
Veteran User
Posts: 7258
Joined: Sat Apr 21, 2007 8:54 pm

Re: x265 Limit threads

Post by mduell »

Yes, although HB also has non-video-encoder threads (video decoder, filters, audio decode and encode, etc).

With x265 the option is `pools`, you can find the syntax in the x265 docs.
andrewk89
Regular User
Posts: 59
Joined: Thu Jun 13, 2013 4:29 pm

Re: x265 Limit threads

Post by andrewk89 »

What about just using Task Manager to lower the priority of the Handbrake thread to Below Normal or Low? Or is "Low" priority not low enough that you need to further reduce the x265 pools, too?
User avatar
s55
HandBrake Team
Posts: 9854
Joined: Sun Dec 24, 2006 1:05 pm

Re: x265 Limit threads

Post by s55 »

Andrew is correct. The best solution is to lower priority further.

HandBrake has dozens of threads beyond just the encoder so you can still hit the CPU hard enough with lower thread counts to cause gaming to be a non starter.
delicious_storage
Posts: 5
Joined: Sat Jan 04, 2020 5:27 pm

Re: x265 Limit threads

Post by delicious_storage »

andrewk89 wrote: Mon Jan 06, 2020 5:09 pm What about just using Task Manager to lower the priority of the Handbrake thread to Below Normal or Low? Or is "Low" priority not low enough that you need to further reduce the x265 pools, too?
Lowering the priority to the lowest setting doesn't work very well for gaming.
s55 wrote: Mon Jan 06, 2020 5:32 pm Andrew is correct. The best solution is to lower priority further.

HandBrake has dozens of threads beyond just the encoder so you can still hit the CPU hard enough with lower thread counts to cause gaming to be a non starter.
While it does use more threads beyond the encoder, they don't completely saturate a core with 100% utilization like the video encoder does.
akyhne
Posts: 26
Joined: Sat Feb 08, 2020 1:02 am

Re: x265 Limit threads

Post by akyhne »

Just right click in Task Manager -> Details on Handbrake.exe and you will be able to deselect multiple threads for HB to use.
https://www.thewindowsclub.com/processo ... ty-windows
Post Reply