PRIMECLUSTER Global File Services Configuration and Administration Guide 4.1 (Solaris(TM) 10 Operating System)

1.8.11 Notes on writing file data on the GFS Shared File System

The GFS Shared File System uses extent based area management. If a file has many extents, some of extents are stored as indirect blocks in V-data area.

In this case, an allocation of new blocks could induce a rebuilding of indirect block. It would consume many V-data area. To prevent V-data starvation, GFS prevents an allocation of new block when V-data area usage exceeds 80%. In this case, a system-call (e.g. write(2)) which attempts to allocate a new block fails with ENOSPC.

Deleting unused files or directories or moving them into other file systems helps you to reduce V-data area usage.

For information on how to check usage of V-data area, see df_sfcfs(1M).