pSeries

pSeries is IBM's line of POWER-based servers that emerged in the late 1990s as the successor to the RS/6000 family. Built around IBM's POWER processors, the pSeries lineup included enterprise-grade systems designed for workloads such as databases, ERP, and large-scale web applications. The platforms supported multiprocessor configurations and scalable memory, with emphasis on reliability and availability.

pSeries systems run multiple operating systems, including AIX, IBM i, and Linux. IBM's POWER virtualization technology, PowerVM, provides logical partitions (LPARs) to run multiple OS instances on a single server, often with high availability via PowerHA and related clustering solutions. Storage, networking, and virtualization features were integral to the platform to support consolidation and enterprise deployments.

In the market, pSeries competed with other enterprise RISC/Unix server lines such as Sun SPARC and HP-UX Integrity servers. Over time IBM integrated pSeries into the broader POWER Systems branding, continuing with POWER7, POWER8, and newer processors. The pSeries designation was gradually phased out as IBM unified its server lineup under POWER Systems, though many of its models live on in current POWER-based offerings and architectures.

See also: RS/6000, POWER architecture, AIX, IBM i, Linux on Power, PowerVM.