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Disable Firefox Disk Cache Completely

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Hello, I recently purchased a SSD and I am using it. I was shocked to see that my SSD's TBW was 800GB in just 2 months whereas I never write any big files and then I realize that Firefox was eating my TBW and I have disabled some features in "about:config".

Those features are: browser.cache.disk.enable = false browser.cache.disk_cache_ssl = false browser.cache.memory.enable = true


But disabling those things did not helped me. I am trying to save my TBW. I want Firefox to never write anything in my SSD. I want to disable cache forever. I want Firefox to store all cache in Memory. I know it will take more internet bandwidth but no problem for me.

Can I tweak these settings in about:config?

browser.cache.disk.capacity = 0 or 1 (Not use if 0 means unlimited or disable in Firefox so I am using 1 and please tell me how what does 0 does) browser.cache.disk.content_type_media_limit = 0 or 1 (Not sure what this is) browser.cache.disk.enable = false browser.cache.disk.free_space_hard_limit = 0 or 1 browser.cache.disk.free_space_soft_limit = 0 or 1 browser.cache.disk.max_chunks_memory_usage = 0 or 1 browser.cache.disk.max_entry_size = 0 or 1 browser.cache.disk.max_priority_chunks_memory_usage = 0 or 1 (Not sure what this is) browser.cache.disk.metadata_memory_limit = 0 or 1 (Not sure what this is) browser.cache.disk.preload_chunk_count = 0 or 1 browser.cache.disk.smart_size.enabled = false browser.cache.disk_cache_ssl = false browser.cache.offline.capacity = 1 browser.cache.offline.enable = false browser.cache.offline.storage.enable = false

Can I create a new setting like browser.cache.disk.disable = true?

Hello, I recently purchased a SSD and I am using it. I was shocked to see that my SSD's TBW was 800GB in just 2 months whereas I never write any big files and then I realize that Firefox was eating my TBW and I have disabled some features in ''"about:config"''. Those features are: '''browser.cache.disk.enable = false''' '''browser.cache.disk_cache_ssl = false''' '''browser.cache.memory.enable = true''' But disabling those things did not helped me. I am trying to save my TBW. I want Firefox to never write anything in my SSD. I want to disable cache forever. I want Firefox to store all cache in Memory. I know it will take more internet bandwidth but no problem for me. Can I tweak these settings in ''about:config''? '''browser.cache.disk.capacity = 0 or 1 '''(Not use if 0 means unlimited or disable in Firefox so I am using 1 and '''please tell me how what does 0 does) '''browser.cache.disk.content_type_media_limit = 0 or 1 '''(Not sure what this is) '''browser.cache.disk.enable = false''' '''browser.cache.disk.free_space_hard_limit = 0 or 1''' '''browser.cache.disk.free_space_soft_limit = 0 or 1''' '''browser.cache.disk.max_chunks_memory_usage = 0 or 1''' '''browser.cache.disk.max_entry_size = 0 or 1''' '''browser.cache.disk.max_priority_chunks_memory_usage = 0 or 1 '''(Not sure what this is) '''browser.cache.disk.metadata_memory_limit = 0 or 1 ''' (Not sure what this is) '''browser.cache.disk.preload_chunk_count = 0 or 1''' '''browser.cache.disk.smart_size.enabled = false''' '''browser.cache.disk_cache_ssl = false''' '''browser.cache.offline.capacity = 1''' '''browser.cache.offline.enable = false''' '''browser.cache.offline.storage.enable = false''' Can I create a new setting like '''browser.cache.disk.disable = true'''?

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All Replies (4)

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The web cache -- temporary copies of html files, images, and other assets used in pages -- is only one part of what Firefox records to disk as you browse. There is a lot of other data, including:

  • Cookies
  • Local storage data set by sites
  • History entries (URL, date, icon)
  • Session history (open and recently closed tabs and windows)

Some SSD users who are paranoid about disk writing have cut down on writes by extending the update interval for session history from 15 seconds to 60 seconds or longer. If you want to try that:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

(2) In the search box in the page, type or paste browser.sessionstore.interval and pause while the list is filtered

(3) Double-click the browser.sessionstore.interval preference to display an editing field, and change the value as desired, then press Enter or click the blue check mark button to save the change.

This value is in milliseconds, so add 000 to the number of seconds:

  • 15 seconds => 15000
  • 60 seconds => 60000
  • 2 minutes => 120000

Whether you should go beyond a couple of minutes depends on how important restoring your previous session -- at startup or after a crash -- is to you as a Firefox feature.


Alternately, you could launch private windows for browsing that you don't want recorded to disk. See: Private Browsing - Use Firefox without saving history.

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So if I am watching a video in YouTube, that video will be stored as cache in my SSD or Memory?

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YouTube sends videos in fragments and it probably instructs browsers not to cache them for very long, if at all. However, you can research what is cached using the about:cache page and see what shows up there after watching a video.