We're calling on all EU-based Mozillians with iOS or iPadOS devices to help us monitor Apple’s new browser choice screens. Join the effort to hold Big Tech to account!

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

This thread was archived. Please ask a new question if you need help.

Firefox on Win 7 64 bit is a big memory hogger; on Win 8.1 32 bit, it's not

Super-Troll
Super-Troll
more options

As above; I have several PCs, on two of which I use FF regularly. One PC has Win 7 64-bit as OS while the other has Win 8.1 32-bit as OS.

I noticed that Firefox on Win 7 64-bit is a big memory hogger, sometimes eating up more than 2GB of RAM and obviously getting into an overflow of some sort after prolonged use. It essentially has some problem regarding memory or chache management, as closing tabs does not lower RAM consumption. It is not possible to leave FF open for days without experiencing this error. In Task Manager, I noticed that when the overflow occurs, FF keeps increasing its memory consumption.

On Win 8.1 32-bit, the above problem does not exist. Closing tabs lowers memory consumption, an overflow does not occur, and leaving the window open for days does not affect performance.

Can anyone help?

As above; I have several PCs, on two of which I use FF regularly. One PC has Win 7 64-bit as OS while the other has Win 8.1 32-bit as OS. I noticed that Firefox on Win 7 64-bit is a big memory hogger, sometimes eating up more than 2GB of RAM and obviously getting into an overflow of some sort after prolonged use. It essentially has some problem regarding memory or chache management, as closing tabs does not lower RAM consumption. It is not possible to leave FF open for days without experiencing this error. In Task Manager, I noticed that when the overflow occurs, FF keeps increasing its memory consumption. On Win 8.1 32-bit, the above problem does not exist. Closing tabs lowers memory consumption, an overflow does not occur, and leaving the window open for days does not affect performance. Can anyone help?

All Replies (1)

Mark Schmidt
Mark Schmidt
more options

Memory leaks are almost always caused by plugins or add-ons. These leaks can be solved by performing a Clean reinstall. This means you remove Firefox program files and then reinstall Firefox. Please follow these steps:

Note: You might want to print these steps or view them in another browser.

  1. Download the latest Desktop version of Firefox from mozilla.org (or choose the download for your operating system and language from this page) and save the setup file to your computer.
  2. After the download finishes, close all Firefox windows (or open the Firefox menu New Fx Menu and click the close button Close 29).
  3. Delete the Firefox installation folder, which is located in one of these locations, by default:
    • Windows:
      • C:\Program Files\Mozilla Firefox
      • C:\Program Files (x86)\Mozilla Firefox
    • Mac: Delete Firefox from the Applications folder.
    • Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory.
  4. Now, go ahead and reinstall Firefox:
    1. Double-click the downloaded installation file and go through the steps of the installation wizard.
    2. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

More information about reinstalling Firefox can be found here.

WARNING: Do not use a third party uninstaller as part of this process. Doing so could permanently delete your Firefox profile data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. These cannot be easily recovered unless they have been backed up to an external device! See Back up and restore information in Firefox profiles.

Please report back to say if this helped you!

Thank you.