Volume or virtual machine level backup and generating placeholders for virtual machine files

An information management system configured to remove files associated with a virtual machine (VM), the system comprising:

• one or more computing devices comprising computer hardware and configured to:
• create a backup copy of data associated with a VM on one or more secondary storage devices, wherein the data associated with the VM resides on a primary storage device and comprises a plurality of files associated with the VM, and wherein the backup copy comprises corresponding secondary copies of the plurality of files;
• generate first metadata associated with the backup copy, wherein the first metadata indicates, for each respective file included in the backup copy, when the respective file was last modified or accessed;
• identify, based on the first metadata associated with the backup copy and without accessing the data associated with the VM residing on the primary storage device, a set of candidate files from the plurality of files that are eligible to be removed from the primary storage device;
• and
• for each candidate file in the set of candidate files identified based on the first metadata associated with the backup copy and without accessing the data associated with the VM residing on the primary storage device:
• determine, based on second metadata associated with the candidate file stored on the primary storage device, whether the candidate file has changed since a first time at which the backup copy including the candidate file was created;
• in response to determining that the candidate file has not changed since the first time at which the backup copy including the candidate file was created, remove the candidate file from the primary storage device;
• and
• add a file placeholder for the removed candidate file on the primary storage device.