Chris Johns Email & Phone Number

Minneapolis, Mn, Us

Minneapolis, Minnesota, United States

Greater Minneapolis-St. Paul Area

Formed my own company to help people in my extended neighborhood with issues with Apple Mac computers and with home networking, including hardware repairs and upgrades, software issues, user training, and turning a sad user of a slow or broken Mac into somebody delighted with their experience.I've had many rave reviews on the Nextdoor website in the western suburbs of Minneapolis.

Greater Minneapolis-St. Paul Area

• Linux kernel development, including turning 75,000 lines of modifications into a set of standalone patches for ease of upgrades and publishing.• Hardware management system work, from user interface down to embedded Linux controllers.• Network resiliency, high availability and failover in a large-scale (10000+ blade) distributed supercomputer.• Integration of Python-based OpenStack with propietary hardware management infrastructure.

Mendota Heights, Mn

My responsibilities at Cassatt were split between the original company focus (high-performance computing) and the new focus (cloud computing):HPC:• Linux kernel work to enhance the implementation of a single-system image (SSI) on a cluster of off-the-shelf rack-mounted servers, to provide a single login and process space across the whole cluster.• Worked on a distributed filesystem (DVS, now in use at Cray Inc. on supercomputers) to allow it to interact correctly with clustered filesystems such as Lustre and GPFS.• Created a binary kernel injection (trampoline) facility to allow the single-system image kernel modules to operate correctly without requiring modified kernel source code.Cloud Computing:• Wrote Java-based software to interact with lights-out BMC firmware, such as HP iLO and Dell DRAC, to discover data center hardware and allow servers to be powered on and off under control of the cloud management software.• Created Java-based image management software to allow captured server images to be deployed to diskless or diskful servers on demand.• Implemented the image capture and diskless deployment of server images based on various flavors of Linux, Solaris, AIX, and Windows.

Greater Minneapolis-St. Paul Area

The focus of the software development group in the St. Paul, Minnesota office was the operating system for the new CRS-1 core router product.My responsibilities included:* Implementing a checkpoint/restart library for system components on the CRS-1 to use to store and recovery their state following a failure or failover to a standby hardware blade* Implementing the hardware failover (High Availability) feature for redundant router blades.

Redmond, Wa

I worked briefly in the group productizing the Tiger video-on-demand software from Microsoft Research, until the group was reorganized. I then spent the rest of my time at Microsoft working on the Windows Media Server, which was written in C++/DCOM.

Eagan, Mn

• Distributed operating system development for Cray T3E supercomputer.• Designed and developed process migration feature to load-balance the system.• Designed and developed system-level checkpoint/restart to allow applications to ride through system outages.

Bracknell, Uk

• Central technical support role working with customers throughout the UK supporting system software.• Analyst-in-charge at ECMWF (European Weather Centre), working with scientists and engineers from 18 countries, supporting their work on supercomputer systems.