[gpfsug-discuss] File_heat for GPFS File Systems

[Alex Chekholko]

On 09/27/2016 11:04 AM, Andreas Landhäußer wrote:
> if a file gets hot again, there is no rule for putting the file back
> into a faster storage device?

The file will get moved when you run the policy again.  You can run the 
policy as often as you like.

There is also a way to use a GPFS hook to trigger policy run.  Check 
'mmaddcallback'

But I think you have to be careful and think through the complexity. 
e.g. load spikes and pool fills up and your callback kicks in and starts 
a migration which increases the I/O load further, etc...

Regards,
-- 
Alex Chekholko chekh at stanford.edu