Setting space reservation values for volumes

What space reservation values are

When space reservation values are set for a volume, all subsequent files created in that volume are created with the type of space reservation specified. Reservations can be controlled individually to reserve space for overwrites of existing file data or to reserve space to fill holes in the file (areas in the file that have never been written to). Turning these settings on or off does not change the reservation setting for any existing files in the volume.

Enabling space reservations for volumes

To set space reservation values for new files in a specified volume, complete the following step.

Step	Action
1	Enter either or both of the following commands: *vol options vol_name* reserve_fill {on \| off} vol options vol_name reserve_overwrite {on \| off}** `vol_name` is the volume in which file reservations are set. `reserve_fill on` enables space reservations only to fill holes in new files in vol_name. `reserve_overwrite on` enables space reservations only to overwrite blocks that have already been written in new files in vol_name. Example: vol options vol2 reserve_fill on vol options vol2 reserve_overwrite off

Step

Action

Enter either or both of the following commands:

vol options vol_name reserve_fill {on | off}

vol options vol_name reserve_overwrite {on | off}

vol_name is the volume in which file reservations are set.

reserve_fill on enables space reservations only to fill holes in new files in vol_name.

reserve_overwrite on enables space reservations only to overwrite blocks that have already been written in new files in vol_name.

Example:

vol options vol2 reserve_fill on

vol options vol2 reserve_overwrite off

Querying space reservations for volumes

To find out the status of space reservations for a volume, complete the following step.

Step	Action
1	Enter the following command: vol options vol_name vol_name is the volume in which reservations are set. Example vol options vol2 Result: root, diskroot, nosnap=off, nosnapdir=off, minra=off, no_atime_update=off, raidsize=8, nvfail=off, snapmirrored=off, resyncsnaptime=60, create_ucode=off, convert_ucode=off, maxdirsize=10240, fs_size_fixed=off, reserve_fill=on, reserve_overwrite=off

Step

Action

Enter the following command:

vol options vol_name

vol_name is the volume in which reservations are set.

Example

vol options vol2

Result:

root, diskroot, nosnap=off, nosnapdir=off, 
minra=off, no_atime_update=off, raidsize=8, 
nvfail=off, snapmirrored=off, resyncsnaptime=60, 
create_ucode=off, convert_ucode=off, maxdirsize=10240, 
fs_size_fixed=off, reserve_fill=on, 
reserve_overwrite=off