At IBM, innovation is at the heart of everything we do. As part of IBM's Linux on Z and LinuxONE organization, we are committed to pushing the boundaries of enterprise computing by advancing the Linux operating system on the s390x architecture. Our work supports some of the most secure, scalable, and high-performance platforms in the industry—designed for mission-critical workloads in finance, healthcare, and beyond. Our team operates at the intersection of research and development, working on bleeding-edge technologies that shape the future of Linux on IBM Z and LinuxONE. We specialize in performance engineering, diving deep into system internals to analyze behavior, uncover bottlenecks, and drive optimizations across the stack—from the Linux kernel to virtualization layers like QEMU/KVM. We collaborate closely with upstream communities and internal development teams to ensure that Linux not only runs on IBM Z—but runs exceptionally well. Whether it's tuning for throughput, latency, or efficiency, our work has a direct impact on how modern workloads perform on enterprise-grade infrastructure. If you're passionate about Linux internals, performance analysis, and contributing to open-source development on one of the most sophisticated hardware platforms in the world, we'd love to hear from you.

As a Performance Engineer in our Linux on IBM Z and LinuxONE team, you will play a key role in analyzing and optimizing the performance of complex Linux-based systems.

Your responsibilities will include:

• Conducting performance analysis and evaluation of Linux systems, with a focus on RHEL and Fedora, running on sophisticated system architectures.
• Identifying and resolving performance bottlenecks across multiple layers, including: The Linux kernel, networking, and storage I/O subsystems.
• The QEMU/KVM virtualization stack.
• Utilizing industry-standard low-level benchmarks (e.g., Fio, SPEC, iperf) and performance analysis tools such as sysstat and the z/VM Performance Toolkit.
• Tuning and optimizing configuration parameters across the Linux/KVM stack on IBM Z to improve efficiency and throughput.
• Collaborating closely with developers and stakeholders across the Linux/KVM on IBM Z ecosystem to drive performance improvements.
• Preparing and presenting findings, recommendations, and new ideas to the team in a clear and structured manner.

• A degree in Computer Science, Electrical Engineering, or a comparable qualification.
• Proven experience in performance analysis of complex IT systems.
• Proficiency in scripting languages such as Bash, Python, and/or Ansible for automation and data evaluation.
• Solid programming skills in C/C++, Java, or Go.
• Strong analytical thinking and a structured approach to problem-solving.
• A collaborative mindset and enthusiasm for working across teams.
• Passion for improving systems and driving technical excellence.

In-depth knowledge of kernel architecture, networking, storage systems, scheduling mechanisms, and virtualization technologies. Experience working with enterprise-grade hardware platforms such as IBM Z, x86, or ARM is a strong advantage.