[OpenAFS] "ERROR: Cache dir check failed (cannot use tmpfs as cache partition)"

[Adam Megacz]

Is there a reason why tmpfs isn't supported (1.5.74)?

I was really hoping to start using it for my cache partitions with 1.5.x
and 1.6.  It has all the advantages of memcache plus it can pushed out
to swap when there's memory pressure (which IIRC memcache cannot).

Currently I use "dd" to make a huge image in a tmpfs partition and then
loopback-mount that, but aside from all the overhead of passing through
the VFS layer twice this also means that each page is in memory twice
(once in tmpfs's memory and once in the buffercache).  Indeed,
eliminating this "double buffering" is one of the big selling points of
tmpfs.

Thanks,

  - a