Data Domain: Checking and Changing the Cleaning Throttle

System Cleaning (or Garbage Collection) is an essential part of maintaining a Data Domain system. Properly configuring the cleaning throttle for the environment is essential to optimal system performance.

The default schedule runs the clean operation every Tuesday at 6 a.m. (tue 0600) with 50% throttle. For most installations, this value is sufficient.

The current cleaning throttle can be seen using the Enterprise Manager web interface or the following system command:
 

sysadmin@bane# filesys clean show throttle
           50 Percent Throttle

Cleaning is a file-system operation that impacts overall system performance while it is running. As of DDOS 7.9 and earlier, changing the cleaning throttle does not affect the running cleaning cycle. The change will take effect when the next cleaning cycle is started. This behavior may change in a future release.

To alter the cleaning throttle, use the following command:
 

filesys clean set throttle <percent>

A higher percent value increases the amount of system processing resources that cleaning may consume.

To reset the clean schedule to the default of Tuesday at 6 a.m. (tue 0600), the default throttle of 50%, or both, use the filesys clean reset operation.
 

filesys clean reset {schedule | throttle | all}

If the cleaning throttle is set too high, overall system performance suffers as system resources are allocated more to cleaning than to other system activities. Setting the cleaning throttle too low slows down the cleaning process, causing it to take longer to complete.

For more information, see Data Domain: Scheduling Cleaning on a DDR.