Is it possible to disable file caching when using EFS with Lambda?


Accessing a file concurrently on EFS does not seem to be working as expected. Specifically, any writes to a file does not appear to be read the same from two different Lambda environments.

  • Two Lambda function invocations read the same file on an EFS volume concurrently (different execution environments), they see the same data.
  • Function 1 updates the file and closes the file. Function 1 reads the file and sees the updated data.
  • Function 2 reads the file again, but reads stale data (from nfs cache setting?).

How do I ensure that all function invocations see the newly written data in the file?

  • Looks like I need to set mount options for the NFS client, specifically noac, but I'm not seeing any documentation on how to set NFS mount options with Lambda.

asked 2 months ago33 views