Question:
What would VDS-TC do when the storage reaches to volume usage close to 100%?
Answer:
VDS-TC would start cleaning some of the cached objects based on the following parameters:
1, expiration_high_water_mark: This parameter determines how full the cache data storage can become, based on percentage, before the system performs an expiration task.
By default, the system checks this value at 0400 system time to determine if an expiration task needs to be performed.
If the cache disk volume usage is above this parameter, the expiration task begins to run. The default value for this parameter is 97%.
2, expiration_low_water_mark: This parameter controls at what point the system expiration task can stop removing objects from the cache data storage.
Once the cache disk volume usage falls below this parameter, the expiration task stops running. The default value for this parameter is 92%.
3, volume_critic_water_mark: When the cache disk volume usage reaches the level that is defined by this parameter, as a percentage of disk space used, the application stops writing to this volume.
The default value for this parameter is 98%.
Please note that the cached contents are stored on the network storage, so the cleaning process deals with the network storage instead of the local hard drive of the Cache Engine.