Once upon a time, Brian Wheeler <bdwheele(a)indiana.edu> said:
So, how does this scenario work?
* The machine has 4G of RAM,
* > 50% RAM is being used by actual software (firefox, eclipse, mail
client, etc), so the other < 50% is pagecache
* The machine has 4G of swap, none of which is active.
So then a user drops a 8.5G DVD image into /tmp.
On a traditional /tmp-on-disk if it filled up then you'd get an ENOSPC
and user things can't write to disk, but the OS will be fine since 5% is
reserved for root.
With tmpfs the pagecache will fill up and start to overflow to
swap...until swap fills up. What happens then?
2G gets written and then -ENOSPC. 2G gets pushed to swap.
The default for tmpfs mounts is an fs that is sized to RAM/2.
Chris Adams <cmadams(a)hiwaay.net>
Systems and Network Administrator - HiWAAY Internet Services
I don't speak for anybody but myself - that's enough trouble.