Firefox is killing your SSD

If you use Firefox there is a setting you must change or live with the idea your SSD will die much sooner than it should. M-Tech laptops modern multi-core processor systems and higher quantities of RAM allow our users to open multiple Firefox tabs and windows simultaneously. This can have an unintended effect for Solid State Drives as your sessions store and write data constantly to your NAND.

What the issues are

By default Firefox is writing tirelessly at anywhere between 300K and 2MB per second to a file called "recovery.js”. This is Firefox’s session backup file that is used to restore your browser sessions in case of a browser or an OS crash. That is extremely useful functionality. While the idea is very useful, the amount of writes to your SSD are very heavy. Since SSD's data life are based on writes, your Firefox browser is taking years off your drives lifespan. Depending on what you’ve got open in your tabs, Firefox could be dumping tons of data into recovery.js, cookie* files, or both. Running at 1.1GB for every 45 minutes, you’re looking at ~35GB/day written to your SSD if you leave your machine running. This may not be the worst example of how much data could be going into recovery.js. Tests clocked Firefox at 2MB/s writing to this file and the writing thread never went dead always showing up on the top of the list in Resource Monitor.

The Easy Fix

This behavior is controlled by a parameter that you can access through typing "about:config” in the address bar. This parameter is called: —browser.sessionstore.interval

It is set to 15 seconds by default. In my case, consider setting it to a more sane 30 minutes. After this you should only be seeing about 2GB written to disk when your computer workstation is left idle, which still feels like a lot but is 5 times less than before.

Bottom line is that if you have a lower capacity consumer level SSDs in some of your machines, you may want to check and tweak your Firefox config. Those drives can be rated for about 20GB of writes per day and Firefox alone might be using more than half of that. This is especially true if you have a several browser windows open at all times each with numerous tabs. Changing this parameter may even help with normal HDDs. Your machine will feel faster if it doesn’t have to constantly write this session info. If you are using Firefox and a  SSD you should check this immediately.