Thread: How much space should be free in rootFS?
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reinob is offline reinob
2012-10-25 , 10:36
Posts: 1,808 | Thanked: 4,272 times | Joined on Feb 2011 @ Germany
#8
Originally Posted by pichlo View Post
I seem to remember having heard or read somewhere that you start hitting lockup issues when a system is used to >75% of its capacity. That applies to any system, be it a production line, motorway, network bandwidth or rootfs space.
I'd say it's more the opposite. In general (and specially in a production line), you want to maximize utilisation. Same for bandwidth.

With disk/memory space the issue is a bit more tricky. If you use up all RAM and suddenly more RAM is needed, the allocation will either fail (e.g. if no swap) or take much longer (swapping).

With disk space there is no "swap" concept, so writing will fail. Most programs don't handle errors correctly (if at all, unfortunately), so random programs may randomly crash.

In the particular case of flash memory (rootfs, mmc, emmc), due to the wear levelling, you always need some extra free space so that writing will work.