[gpfsug-discuss] Thin provisioning disks in multi-PB filesystem

[Vladimir]

Hello,

I have two questions regarding support of thin provisioning in GPFS:

1) is anybody tried to use thin provisioned disks in multi-PB file systems?

Upon initial observation, it appears that enabling thin provisioning 
results in noticeable delays during mount operations. These delays are 
roughly equivalent to the time required to read 1% of the total capacity 
of the file system.
I'm concerned about potential drawbacks that could impact performance. 
Have you encountered any issues related to this?

2) is it possible to convert "normal" nsd into "thin provisioned"?

 From mmchnsd man page it seems to be possible, but trying to do so
mmchnsd says "This command cannot be used to change the thin 
provisioning disk type for an NSD." (I'm on PTF 5.1.2-15 on Linux)

I would be grateful for any feedback or insights related to this matter.

Thanks,
Vladimir