Are you seeing high memory usage in Chrome?

We've been getting reports that AdBlock can cause Chrome to run up huge amounts of memory, especially when Chrome is left open for a while with many tabs open. Another symptom of what we believe is the underlying issue is that Chrome and AdBlock frequently crash.


See also: AdBlock is frequently crashing in Chrome


Workarounds

If you see Chrome or AdBlock using alarming amounts of memory or crashing frequently, try one of these suggestions.
  • Open and then close AdBlock's options page.
  • In AdBlock's options, disable EasyList and AdBlock Custom, and then enable them again.
  • Restart Chrome.


The gory details

This doesn't appear to be a memory leak (that is, an application or extension gobbling up more memory than it needs and hoarding the unused memory). We believe it's an issue with how Chrome handles memory. Every tab you open and every extension your browser runs grabs some of the memory available on your computer. Ideally, when a tab is closed or an extension no longer needs the memory it grabbed, the memory is reclaimed and returned to the shared pool by a process known as "garbage collecting."

In this case, it looks as if Chrome is delaying garbage collection. The memory "in use" (but not really being used) keeps growing until Chrome slows down, becomes unstable, or crashes or crashes AdBlock. The browser does free up the memory eventually. It may just take a long time. (Note that browsers generally don't guarantee running garbage collection unless a shortage of available memory forces them to.)

This issue has been reported to Google as a possible bug in Chrome. Whether it will be fixed or when is anyone's guess.

Are you seeing high memory usage in other browsers?

The vast number of ads on the Web means that the filter lists (the lists of ad sources that we use to block ads) have grown to more than 100 MB each. AdBlock loads the filter lists and any custom filters you have into your computer's memory while it starts up to help pages load faster afterward. That causes an initially heavy hit on your computer's memory resources. Then, because AdBlock runs on every tab you open, each new tab takes up a little more memory.


We are actively working on minimizing AdBlock's memory usage. We always keep how efficiently we're using memory in mind when we add new features as well.


There are some steps you can take to minimize AdBlock's initial and ongoing memory usage, too.


1. Disable filter lists you don't need.

2. Close some tabs.
AdBlock must run on every tab to work, so more tabs open means more memory used.
If you need to have lots of tabs open, consider using an extension that suspends unused tabs so that they don't take up resources unnecessarily. The Great Suspender is popular and well-reviewed, but we're sure there are others.

3. Unsubscribe from EasyList and subscribe to EasyList without element hiding.
Along with your subscribed filter lists and custom filters, AdBlock loads a style sheet. This style sheet does two things. It hides ads that can't be blocked, and it makes web pages look better afterward by hiding the spaces where ads would normally appear. (By the way, here's why an empty space sometimes remains after an ad is blocked.) The style sheet is huge, and therefore takes up a lot of memory.

EasyList without element hiding removes the style sheet. This frees up memory; however, you will see more ads (the ones that can't be blocked entirely), and web pages will contain more empty spaces.

To subscribe to EasyList without element hiding:
  1. Click the AdBlock button on your browser toolbar and select Options.
  2. On the FILTER LISTS tab, clear the EasyList check box to unsubscribe from it.
  3. At the bottom of the page, type or paste this in the Or enter a URL box:
    https://easylist-downloads.adblockplus.org/easylist_noelemhide.txt
  4. Click Subscribe.


4. Unsubscribe from EasyList and subscribe to EasyList Lite.

EasyList Lite is a special "stripped down" version of EasyList that we've created specifically to help minimize AdBlock's memory usage. It contains filter rules for just the most frequently visited websites. If you visit a website that is not as well known, you may see some ads there. Ads will be blocked on most of the sites you're likely to visit, however.


EasyList Lite is currently available only in AdBlock for Microsoft Edge.


If you've tried these suggestions and you're still seeing a ridiculous amount of memory in use or the number keeps climbing and doesn't stop, please let us know!