HPC systems are composed of multiple tiers of storage, from the top high performance tier (high speed SSDs) to the bottom capacitive one (tapes). File placement in such architecture is managed through prefetchers (bottom-up) and eviction policies (top-...

Modern, large-scale scientific computing runs on complex exascale storage systems that support even more complex data workloads. Understanding the data access and movement patterns is vital for informing the design of future iterations of existing ...

Observability is a necessary capability of modern distributed systems as it allows us to gain actionable insights about reliability, availability, performance, etc., of the system.

In Software Defined Infrastructure (SDI), virtualization techniques are used to decouple applications and higher-level services from their underlying physical compute, storage, and network resources. The approach offers a set of powerful new ...

ARM servers are becoming increasingly common, making server technologies such as virtualization for ARM of growing importance. We present the first study of ARM virtualization performance on server hardware, including multi-core measurements of two ...

The current pace of innovation in computing makes it difficult to assume a fixed set of requirements for the whole life span of a system. Aggressive technology scaling also imposes additional constraints to modern hardware platforms. An answer to this ...

Memory capacity and demand have grown hand in hand in recent years. However, overheads for memory virtualization, in particular for address translation, grow with memory capacity as well, motivating hardware manufacturers to provide TLBs with thousands ...

The virtual switch is the cornerstone of the today's virtualized data center. As all traffic to and from virtual machines or containers must pass through a vSwitch, it is the ideal location for network configuration and policy enforcement.

The bulk of ...

Thanks to the compelling economics of public cloud storage, the trend in the IT industry is to move the bulk of analytics and application data to services such as AWS S3 and Google Cloud Storage. At the same time, customers want to continue accessing ...

Hyper-converged storage is the state-of-the-art for enterprise deployments. VMware's vSAN is the industry leader in this space. This article takes a look at some of vSAN's internal architecture and analysis frameworks to illustrate how modern ...

System software overheads in the I/O path, including VFS and file system code, become more pronounced with emerging low-latency storage devices. Currently, these overheads constitute the main bottleneck in the I/O path and they limit efficiency of ...

Existing operating systems share a common kernel text section amongst all processes. It is not possible to perform kernel specialization or tuning such that different applications execute text optimized for their kernel use despite the benefits of ...

With the emergence of both power and performance as primary design constraints, energy efficiency has become the new design criteria. A platform with heterogeneous-ISA processors can provide multiple power-performance execution points needed for a ...

Among all classes of parallel programming abstractions, lock-free data structures are considered one of the most scalable and efficient thanks to their fine-grained style of synchronization. However, they are also challenging for developers and tools to ...

Kernel probes allow code to be inserted into a running operating system kernel to gather information for debugging or profiling. Inserting code into the kernel raises a number of safety issues. Current solutions follow one of the two paths: a VM-based ...

Despite a number of radical changes in how computer systems are used, the design principles behind the very core of the systems stack--an operating system kernel--has remained unchanged for decades.We run monolithic kernels developed with a combination ...

Transient hardware faults in computer systems have become widespread as shrinking structures and low supply voltages reduce the amount of energy needed to trigger a fault. This paper describes the latest improvements of a software-based fault-tolerance ...

There is a vast number and variety of file systems currently available, each optimizing for an ever growing number of storage devices and workloads. Users have an unprecedented, and somewhat overwhelming, number of data management options. At the same ...