1663351 - High initial memory usage

Status: REOPENED

(Core :: Graphics, defect)

Description

[Michel Le Bihan]

Attachment: Screenshot_win10_2020-09-06_20:45:10.png

Hello,
I noticed that initial memory usage of Firefox is much higher than that of other browsers. I removed Firefox appdata folder to get a clean start, then I changed the startup page to blank. It's 1.5x bigger than that of original Edge and more than 4x higher than that of Chrome. It's quite a lot especially if somebody has a budget 2GB or 4GB mobile device and doesn't keep many tabs open. That memory difference actually even increases compared to Chrome and stays similar compared to original Edge when I navigate to some sites and open additional tabs (same sites on all browsers).

Comment 1

[Alexandra Martin]

Hi,

Thank you for taking the time to submit this bug report. Testing was done on Windows 10 x64bit and MacOS 10.14 with Firefox Nightly 82.0a1 (20200911093056), Beta 81.0b9 (20200910180444), and Release 80.0.1 (20200831163820) and initial memory usage seems to be higher when starting a new profile with a blank new tab, which decreases over time, if browser is not used.

I've assign a component, but if it's not relevant, please feel free to change it to an appropriate one.

Comment 2

[Miko Mynttinen]

Although we have ongoing projects to reduce memory footprint as part of Fission, I find it unlikely that the initial memory usage would change much.
It is also unlikely that this is a problem: modern operating systems optimize memory usage and performance by caching files and swapping out programs as needed, which means that unused memory is wasted memory.

Comment 3

[Michel Le Bihan]

I disagree about the last part. In some regions of the world 2GB and 4GB devices are still quite popular. Especially mobile devices. On those devices you basically don't have unused and wasted memory. You can't just say to those users to get a modern device.

What is Firefox doing during the first launch, displaying a blank page that requires that much memory?

Comment 4

[Miko Mynttinen]

(In reply to Michel Le Bihan from comment #3)

On those devices you basically don't have unused and wasted memory.

With this I was referring to the concept of virtual memory1. For example, if an application is minimized to background, it is likely that the operating system will copy the application's resources from RAM to hard disk, so that RAM can be used by something currently running on foreground.

What is Firefox doing during the first launch, displaying a blank page that requires that much memory?

Developers often face trade-offs between performance and memory usage. For example new tabs are preloaded by default, so that they open faster. Similarly multiple content processes are spun up, because they allow for more security and performance, especially with multi-core systems.