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I can't reset the browser.cache.frecency_experiment setting

  • 6 replies
  • 4 have this problem
  • 20 views
  • Last reply by cor-el

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I tried pretty much everything from https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save http://kb.mozillazine.org/Preferences_not_saved Everything involving prefs.js and user.js. Obviously I'm not interested in reseting my Firefox completely. My system is clean according to Comodo CCE, MBAM and adwcleaner.

Anyway, when I'm resetting the setting in about:config it keeps resetting to user set 4 OR 3. I recall I've set it manually to some value months ago.

I tried pretty much everything from https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save http://kb.mozillazine.org/Preferences_not_saved Everything involving prefs.js and user.js. Obviously I'm not interested in reseting my Firefox completely. My system is clean according to Comodo CCE, MBAM and adwcleaner. Anyway, when I'm resetting the setting in about:config it keeps resetting to user set 4 OR 3. I recall I've set it manually to some value months ago.

All Replies (6)

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Hello effgo, any luck if you change the value to -1 ? (no experiment)

https://mxr.mozilla.org/mozilla-release/source/netwerk/cache2/CacheObserver.cpp#181

thank you

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ideato said

Hello effgo, any luck if you change the value to -1 ? (no experiment) https://mxr.mozilla.org/mozilla-release/source/netwerk/cache2/CacheObserver.cpp#181 thank you

-1 did it. Isn't it a bug though? Doesn't the 'experiment' mean it's an unstable, experimental feature? If yes, then the 'Reset' command should set it to "-1". Should I file a bug report?

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I think that it has to do with cache management and deciding whether to decay cache entries (i.e. HalfLife) The default to check this is 6 hours and can be increased to 50 days.

1759 // Play with different values of the decay time and get telemetry,
1760 // 0 means to randomize (and persist) the experiment value in users' profiles,
1761 // -1 means no experiment is run and we use the preferred value for frecency (6h)
1762 pref("browser.cache.frecency_experiment", 0);
89 // The half life used to re-compute cache entries frecency in hours. 90 pref("browser.cache.frecency_half_life_hours", 6);

Modified by cor-el

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Thanks for the info but right now I'm interested more in a stable experience.

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You can try to set the pref to -1 (or 1: 6 hours) on each Firefox start via a user.js file.

user_pref("browser.cache.frecency_experiment", -1);

You can also check the browser.cache.frecency_half_life_hours pref.