On Fri, Jun 1, 2012 at 7:05 AM, Gregory Maxwell <gmaxwell(a)gmail.com> wrote:
Thats not true (and I've used tmpfs for tmp for years, so I'm
speaking
from experience)— tmpfs is backed by swap on demand. Just add the
space that you would have used for /tmp to your swap.
I am _very_ concerned about large files in conjunction with tmpfs
usage for general purpose /tmp by default. Especially on multi-user
capable systems.
As a sysadmin...for a multi-seat configuration in a home network
environment...do I really need to anticipate maximum large file tmp
usage in calculating my swap partition size for my multi-user family?
8 gigs of ram... so to be safe I want to set up a swap of what...100
gigs to account for a potentially large /tmp of some maximum size?
Does swap backed tmpfs as /tmp currently jeopardize my system's health
by making swap backup for in-memory processes compete with tmp files?
If my users clog up /tmp will that reach a point where the kernel's
oom process killer decided to start killing off running processes
instead of throwing crap out of /tmp?
What happens when I have 2 users who are both downloading dvd iso
sized images into /tmp as well as other things going on. Remind me...
where does firefox by default cache in progress downloads for the
"Open in" facility. Isn't it down in tmp? Do I really want things
like firefox downloads paging out ram into swap and causing an overall
system slowdown?
Without more information about how gracefully /tmp spill over into
swap is handled, I'm inclined to say this really looks problematic as
a default.
And that's not even getting into the more complex issues of virtual
machine configurations which typically run under heavier ram
constraints than disk constraints.
-jef