Starting Mozilla Firefox creates multiple firefox.exe in Task Manager. The E10s fix doesn't solve the issue. Please help.
I am on Windows 10
Additional System Details
- Shockwave Flash 32.0 r0
- User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Firefox/68.0
This is normal. Multi-processing (aka e10s) has rolled out to all users at this point. It keeps your web content in different processes. This has a number of security, performance and stability benefits.
If you want to limit the number of Firefox processes on your system, you can deselect the Use recommended performance settings option in the Firefox settings and toggle the Content process limit setting. You may need to restart Firefox to see the effect.
You will always have multiple processes, even if you set the limit to 1. There will be a separate process for the Firefox program, graphical content, browser extensions and web content. The only processes that you can limit are the web content processes, but doing so may have a negative performance impact.
It's usually advisable to use the Use recommended performance settings so that Firefox can automatically adjust itself for optimal performance on your system.
Hope this helps.
What is the minimum number of processes that you would recommend? I would like to bring the CPU usage to below 30% because sometimes I run Firefox in the background while doing some 3D modelling and rendering work. (Currently on 11 firefox exes and >55% CPU usage)
It is quite normal to see more Firefox processes running.
- one process for the main Firefox thread (user interface)
- one or more content processes, see:
Options/Preferences -> General -> Performance
remove checkmark: [ ] "Use recommended performance settings"
- one process for the compositor thread
- one process for the WebRender when this feature is enabled
You can find the current multi-process state on the Troubleshooting Information page (about:support).
- "Help -> Troubleshooting Information" -> "Application Basics":
See also the Remote Processes section further down for more detail.
You can check the about:support page (Graphics) to see whether WebRender is active. You can set this pref to false on the about:config page to disable WebRender.
- gfx.webrender.force-disabled = true
There are a lot of reasons that Firefox might be using too much CPU. Generally, I wouldn't recommend changing the number of processes. But you are welcome to try. There are a number of factors to consider, so I can't really recommend how many processes will be optimal in your specific situation.
Instead, I'd refer you to this document about reducing CPU usage. Browser extensions are the biggest cause of CPU usage increases that I've seen, although having a resource-heavy website running in a tab can also be a huge consumer.
I find that playing videos in Firefox really hurts performance when I'm doing 3D modelling. It's not as big of an issue for me when I'm rendering because I am fortunate enough to have a graphics card that allows me to render with my GPU instead, but if you are doing the actual rendering with the CPU, then anything running in the background is likely to have a big impact.
You can use the Firefox Task Manager to see what tabs or extensions are using the most resources. This will help you diagnose the problem.
Modified by Wesley Branton