When os.walk() Freezes: Diagnosing and Fixing Silent Network Hangs on NetApp Shared Storage with Python

The Problem Our team manages a NetApp shared storage cluster holding operational data for approximately 1,500 entities. Each entity has its own directory subtree, split by record type and date, resulting in a tree of roughly 4,500 leaf directories per date. Each leaf directory held tens of small .txt files — each containing a JSON array of records dumped by a backend service — scattered across the tree with no consolidation. The file count had grown to a point where NetApp itself started reporti