Skip to main content
NetApp Knowledgebase

What is a PIT file in Data ONTAP?

Views:
49
Visibility:
Public
Votes:
0
Category:
ontap-9
Specialty:
perf
Last Updated:

Applies to

  • ONTAP 9
  • Clustered Data ONTAP 8.3
  • Data ONTAP 7-mode
  • Any NAS or SAN protocol

Answer

  • A Point-In-Time (PIT) file is a special file used for ODX or Copy Offload procedures.
    • This is also called VAAI Storage Acceleration in ESX.
  • Copy Offload is the process of sending only control data from the client to ONTAP while copying from one folder to another on the same storage node.
    • The contents of the file are transferred internally in ONTAP and the client requests the blocks to be transferred.
    • This is used instead of sending the whole file over the network.
    • This can speed up performance compared to the network, particularly in high client or network load situations
  • The PIT file is the container which ONTAP uses to copy the blocks internally from one folder to another

Additional Information

  • TR-4191 page 11 and 21 discuss further about the PIT file
  • ONTAP may delete the PIT file in rare situations, such as a SnapMirror break. When this happens, an EMS message will be logged similar to this:
    • Thu Sep 24 03:07:09 -0600 [node1: token_mgr_admin: token.pit.file.deleted:notice]: PIT file in volume vol1 was deleted.