yum with recent soas builds on XO-1

[Mikus Grinbergs]

Disclaimer:  I am not asking for help;  I am sharing my experiences.

Apparently irrespective of the content of /etc/fstab, recent 
F11-on-XO1 builds are _mounting_ /var/cache/yum as a tmpfs.  What 
gets placed into /var/cache/yum is the "indexes" of the 
repositories, plus actual packages as they are being downloaded.

On my XO-1s, tmpfs "partitions" (including for /var/cache/yum) are 
given 110 MB.  For the os5 build (and previous versions), only the 
"primary" sqlite data (per repository) get saved in /var/cache/yum 
(this file for fedora is 38 MB) -- leaving room for yum to go about 
its business.  But for the SoaS3 20090807 build (and previous 
versions), often (but not always) yum fetches additional "listfile" 
sqlite data (per repository) into /var/cache/yum (this file for 
fedora is 68 MB) -- and this additional fetch (for fedora) fails 
(runs out of room), causing yum to terminate abruptly (leaving 
/var/cache/yum at 100% occupancy).

I do not know how come yum on SoaS3 tries to stuff that additional 
huge file into /var/cache/yum, when os5 does not -- but tmpfs on my 
XO-1 is *definitely* not big enough.  The result is that on my XO-1 
I have to manually "relocate" what /var/cache/yum holds, before I 
can consistently use 'yum' with recent soas builds.

mikus