ViewSys is a legacy, interactive system monitoring utility for HPE NonStop servers that provides real-time visibility into system resource utilization. Similar to PEEK and Measure, it allows system operators to view resource consumption as it happens, allowing for immediate analysis of the impacts of process relocations or controller path changes. 

HPE NonStop ViewSys Overview

• Purpose: Monitors system resources, including processor utilization, I/O performance, and memory usage, on NonStop systems.
• Key Features: Provides online viewing of system resources, allowing for quick recognition of performance bottlenecks, which helps in performance tuning.
• Functionality: Unlike Measure, which is typically analyzed offline, ViewSys offers an interactive, live, and graphical view of system performance.
• Operation Requirement: Runs from HPE block mode terminals or non-Stop terminal emulators, presenting average resource usage for each polling interval. 

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Detailed Historic Timeline: ViewSys & NonStop Monitoring Evolution

The history of ViewSys is deeply intertwined with the development of the HPE NonStop OS and its monitoring toolkit.

Era 1: Tandem Era (The Early Days)

• 1976: Initial Tandem NonStop System introduced; basic system monitoring is manual and console-based.
• 1980s (Mid-late): As Transaction Monitoring Facility (TMF) and Pathway are introduced, the need for interactive monitoring grows.
• 1990s: ViewSys becomes a key utility for operators managing massive OLTP (Online Transaction Processing) workloads. 

Era 2: Compaq/Early HP Era (The Transition)

• 1997: Compaq Acquires Tandem.
• 2003: HP Acquires Compaq. The monitoring focus begins to merge with Integrity-based architecture.
• 2004: The ViewSys User’s Guide highlights ViewSys alongside PEEK and Measure, standardizing its use for interactive monitoring.
• 2005: Introduction of HP Integrity “NonStop i” (TNS/E) servers using Intel Itanium processors. ViewSys adapted to monitor Itanium systems. 

Era 3: Modern HPE Era (The Modernization) 

• 2014: First NonStop X (TNS/X) systems on x86-64 are introduced. ViewSys remains a available tool, but modernization efforts begin.
• 2015: Hewlett Packard Enterprise (HPE) is formed.
• 2016-2020: Shift towards Web ViewPoint Enterprise (by Idelji Corporation), which provides web-based dashboards for monitoring EMS events and system metrics.
• 2020: Sales of Itanium-based systems end. Modern monitoring focuses heavily on NonStop X systems and virtualized environments.
• Present: While legacy ViewSys may exist in older environments, it is largely superseded by modern GUI-based, browser-independent monitoring solutions like Web ViewPoint and Remote Analyst. 

HPE NonStop ViewSys Overview and Timeline by Era