Category Archives: portfolio

Hybrid Storage Pools: Using Disk and Flash with ZFS

Adam Leventhal of Delphix speaking at ZFS Day.

In 2008, the ZFS Storage Appliance (nee the Sun Storage 7000) was one of the first architectures to add flash SSDs between the existing tiers of disk and memory. The Hybrid Storage Pool (HSP) offered completely new economies, but with both known and unknown idiosyncrasies. Adam Leventhal, the inventor of the HSP, will talk about their functionality and utility, pitfalls and shortcomings, as well as the next steps for ZFS amidst an ever changing landscape of technologies and economics.

ZFS Day: Architecting ZFS Solutions

Richard Elling at ZFS Day.

The ZFS hybrid storage pool model is very flexible and allows many different combinations of storage technology to be used. This presents a dilemma to the systems architect: what is the best way to build and configure a pool to meet business requirements? We’ll discuss modeling ZFS systems and hybrid storage pools at a datacenter scale. The models consider space, performance, dependability, and cost of the storage devices and any interconnecting networks (including SANs). We will also discuss methods for measuring the performance of the system.

Performance Analysis: The USE Method

Brendan Gregg’s talk at FISL, July 2012.

This talk introduces the USE Method: a simple strategy for performing a complete check of system performance health, identifying common bottlenecks and errors. This methodology can be used early in a performance investigation to quickly identify the most severe system performance issues, and is a methodology the speaker has used successfully for years in both enterprise and cloud computing environments. Checklists have been developed to show how the USE Method can be applied to Solaris/illumos-based and Linux-based systems.

Many hardware and software resource types have been commonly overlooked, including memory and I/O busses, CPU interconnects, and kernel locks. Any of these can become a system bottleneck. The USE Method provides a way to find and identify these.

This approach focuses on the questions to ask of the system, before reaching for the tools. Tools that are ultimately used include all the standard performance tools (vmstat, iostat, top), and more advanced tools, including dynamic tracing (DTrace), and hardware performance counters.

Other performance methodologies are included for comparison: the Problem Statement Method, Workload Characterization Method, and Drill-Down Analysis Method.