RPC 13: OST_STATFS
~~~~~~~~~~~~~~~~~~
[[ost-statfs-rpc]]

OST_STATFS ('pb_opc' = 13) is an RPC that queries data about the
underlying file system for a given OST. It's form and use are nearly
identical to the MDS_STATFS RPC. Refer to <<mds-statfs-rpc>> for
details. The only differences in OST_STATFS are that it has a distinct
'pb_opc' value, it carries information about an OST (instead of an
MDT).  The MDT may send regular OST_STATFS RPCs to each OST in order
to keep its information about free space and utilization updated.
That allows the MDS to make more optimal file allocation decisions.