On 23/12/15 12:47, Oesterlin, Robert wrote:
I’m talking about the case where the storage device uses thin-provisioning internally to allow for better utilization. In this particular case the vendor array uses thin-provisioning, and I don’t have an option to turn it off.
In which case I would argue that the storage array is unsuitable for use with GPFS if having that space reserved for GPFS is a problem for you.
But to answer your question if GPFS does not send TRIM/UNMAP commands to block devices this is exactly what you would expect just like any other file system that does not do discards. Depending on how "smart" the storage array is, it might spot if you write zeros all over and reclaim the space.
My understanding of GPFS is that you want relatively dumb storage devices that don't do or at least can be turned off fancy stuff like thin provisioning, tiering, flash cache's etc. because this just gets in the way of GPFS.
JAB. -- Jonathan A. Buzzard Email: jonathan (at) buzzard.me.uk Fife, United Kingdom. _______________________________________________ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
