swap_memory() tries /proc/stat if /proc/vmstat missing

[dpavlenkov]

In joyent's SmartOS LX-brand zones, /proc/vmstat is missing but /proc/stat is available.

[giampaolo]

Mmmm.. on Ubuntu 14.04 that's not available:

~/svn/psutil {master}$ cat /proc/stat | grep swap
~/svn/psutil {master}$

[dpavlenkov]

/proc/stat -> swap is available in Joyent's LX zones. On real ubuntu /proc/vmstat is available. This doesn't affect real linux behavior, but it fixes LX zones.

[giampaolo]

I guess I'm completely ignorant about this SmartOS / LX zones. Can you elaborate on what this patch is trying to fix/address and on what operating systems?

[dpavlenkov]

https://docs.joyent.com/public-cloud/instances/infrastructure/images
https://wiki.smartos.org/display/DOC/LX+Branded+Zones

Lx branded zones are linux containers on illumos. They should work like native linux, but that's work in progress. Some features are missing like /proc/vmstat . So, at first swap_memory barfed. You fixed that. Now this PR is about getting useful numbers for sin sout. They are available in /proc/stat.

[dpavlenkov]

Let's hold this thought. I haven't seen non-zero values for sin/sout. If I can't get numbers, then this patch is moot.

[dpavlenkov]

Closing PR because swap in/out are not available on this platform.