Data Domain DD400 Series, User Manual

Page: 122 / 300

Clean Operations
84 DD400 Series Restorer User Guide
You can run the
clean
operation for a set number of hours or until a set number of gigabytes are
available on the restorer. The default amount of cleaning done (and maximum allowed in one
operation) is 25% of the total data capacity of the restorer. When the operation finishes, it sends a
message to the system log giving the percentage of storage space that was cleaned and the amount
of free space available.
Note Any operation that shuts down the restorer file system, such as the
filesys disable
command, or that shuts down the restorer, such as a system power-off or reboot, stops the
clean
operation. The
clean
does not restart when the system and file system restart.
Either manually restart the
clean
or wait until the next scheduled start.
The operation has six phases:
•
Phase one makes a preliminary selection of data to clean. Phase one on average takes 10 to 40
minutes.
•
Phase two goes through all of the files on the system and determines what should remain and
what should be removed. Phase two can take up to three hours.
•
Phase three writes any pending index-metadata to disk. Phase three on average takes two to
four minutes.
•
Phase four removes any duplicate data segments that may be left behind when a clean process
is interrupted. Phase four on average takes 15 to 45 minutes.
•
Phase five makes clean copies of all files that hold live data and creates new indexes. Phase
five on average take 40 to 60 minutes.
•
Phase six regenerates internal restorer data structures. Phase six on average takes about 90
minutes.
Start Cleaning
To manually start the
clean
process, use the
filesys clean start
operation. With no
options, the operation uses the current setting for the scheduled automatic
clean
operation and
cleans up to 25% of the total space available for data. If the system is less than 25% full, the
operation cleans all data. Administrative users only. The options are:
•
Run the operation for a given number of hours.
•
Recover disk space until a given number of gigabytes (a total of newly cleaned and previously
unused space) is available for data storage.
•
Begin the cleaning with no warning messages or prompts (the
nowait
option).
Using a
filesys clean start
option for hours or gigabytes free does not change the setting
for the scheduled automatic
clean
operation.