460K VSAM Records in 25 Seconds: Rethinking VSAM → PostgreSQL at Enterprise Scale

What really slows down IBM Z modernization? It's not the application code — it's the data. In this episode of Skyward Data, VirtualZ Co-Founder Dusty Froyum and Marc Sokol (Executive Chairman, former SVP at CA Technologies) break down what actually happens inside enterprise VSAM-to-PostgreSQL migrations, and why the data layer is the hardest part to get right. Drawing on decades in the mainframe world, Marc Sokol explains why so many migration programs stall at the data layer — data dependencies, stale datasets, and heavy ETL or CDC architectures turning a "simple migration" into a complex one. Dusty Froyum outlines how a no-code, direct-access approach simplifies the architecture, reduces operational complexity, and helps teams hit tight migration windows without over-engineering. In this episode of Skyward Data, the podcast from VirtualZ Computing: - Why data, not code, is what delays mainframe modernization - Real results: 460,000 VSAM records moved to PostgreSQL in 25 seconds - 60.9 million records delivered in 18 minutes — roughly 56,000 records per second sustained - The hidden complexity behind migrations that look simple at the outset - How to avoid overbuilt ETL and CDC architectures, and move data incrementally without disruption This direct-access, no-code approach is delivered by PropelZ, VirtualZ's tool for moving and replicating IBM Z mainframe data — including VSAM — to the cloud and to targets like PostgreSQL, with no code and no homegrown pipelines. PropelZ is part of VirtualZ Computing's no-code portfolio for enterprise mainframe data, alongside Lozen (live in-place data access), FlowZ (cloud storage for backup and archive), and Zaac (cloud and SAN as native z/OS storage). Topics: IBM Z modernization, VSAM, PostgreSQL, mainframe data migration, ETL alternative, CDC, no-code data integration, incremental data movement, z/OS, hybrid cloud. Listen to more Skyward Data episodes: https://virtualzcomputing.com/podcasts/