Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

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

Basic web page caching has major performance issues.

  • 6 replies
  • 6 have this problem
  • 13 views
  • Last reply by james.lemay

more options

For about two years now, i have noticed that Firefox gets more and more sluggish with each web page that is opened. Yet despite that web pages and tabs are closed, Firefox hangs on to that cache and never releases it until memory runs out, or it ultimately crashes. As the number of pages increase, CPU consumption goes up and up, and memory goes allocation goes up and up. Why not just release the memory after each page is closed? The worst case I have had is when 10 or more browser instances are opened with numerous tab and reused for days. All physical memory is used up and spilling over to hard drive caching which makes slower by a factor hundreds of times slower. I have used Windows laptops and PCs, from version 7 to 10. They all experience the same problem. Are you aware of this? Even Microsoft and other companies warn users about this performance issue. Eventually, every Firefox browser instance needs to be closed to start from scratch again... that is if I can even get the keyboard to respond. Everything slows to a crawl.

For about two years now, i have noticed that Firefox gets more and more sluggish with each web page that is opened. Yet despite that web pages and tabs are closed, Firefox hangs on to that cache and never releases it until memory runs out, or it ultimately crashes. As the number of pages increase, CPU consumption goes up and up, and memory goes allocation goes up and up. Why not just release the memory after each page is closed? The worst case I have had is when 10 or more browser instances are opened with numerous tab and reused for days. All physical memory is used up and spilling over to hard drive caching which makes slower by a factor hundreds of times slower. I have used Windows laptops and PCs, from version 7 to 10. They all experience the same problem. Are you aware of this? Even Microsoft and other companies warn users about this performance issue. Eventually, every Firefox browser instance needs to be closed to start from scratch again... that is if I can even get the keyboard to respond. Everything slows to a crawl.

All Replies (6)

more options

See if this helps;

Type about:preferences#privacy<enter> in the address bar. The button next to History, select Use Custom Settings.

At the bottom of the page, turn on Clear History When Firefox Closes. At the far right, press the Settings button. Turn on Cache and Form And Search History.

more options

Fred,

Thanks for the response. However, I am trying to weigh whether mere history links for a day or two of browsing a 100 web pages would swell to a size of 2GB in RAM. The cache seems to be storing all html information to get to that size. So what is the definition of "history"? Is it just a list of URLs or does it mean the entire web page contents are stored in RAM? Content cache is usually stored on disc, yes? I restarted Firefox yesterday and right now I just have two instances open with a total of four tabs. CPU usage is a mere 0.3% and memory usage is 108.5MB. I can easily live with that. However, in my work, the pages are live and constantly update. After a few days, the CPU will rise to 30% or more constantly and it noticeably affects other programs. It is not until the very last tab is closed when Firefox releases all that memory.

.. Jim..

more options

james.lemay said

So what is the definition of "history"? Is it just a list of URLs or does it mean the entire web page contents are stored in RAM?

In a manner of speaking, both

The History Manager <Control> H stores all the links your browser displays.

The cache stores all information about the web page. This is retained for a time in case you revisit the same page.

more options

Fred, Okay, but the content of the web page should be stored on disk, right? I assume the content will stay in RAM as long as the page is being viewed. But after the tab/browser closes, RAM should release its copy of the content because it is no longer needed, right? ..Jim ..

more options

Boot the computer in Windows Safe mode with network support to see if that has effect in case security software is causing problems.

more options

Thanks for your response. The issue does not occur when I open the first instance of Firefox. It gradually occurs days later after I have left several browser windows and tabs open with constant use. I cannot use my work laptop to do test this because of the risk factor with no security software. We use McAfee Enterprise software with Windows 10. I also have a work desktop with Windows 7 (with the same McAfee), and a home desktop with Windows 7 which uses AVG. All have the same problem. I use CCleaner on the home desktop so the cache is usually deleted.