Showing 107 results for Author: Sarp S. Oral
Sep, 2011
Conference Paper
This paper discusses the business, administration, reliability, and usability aspects of storage systems at the Oak Ridge Leadership Computing Facility (OLCF). The OLCF has developed key competencies in architecting and administration of large-scale Lustre deployments as well as HPSS archival systems. Additionally as these systems are architected, deployed, and expanded ov…
Jun, 2011
Conference Paper
As storage systems get larger to meet the the demands of petascale systems, careful planning must be applied to avoid congestion points and extract the maximum performance. In addition, the large size of the data sets generated by such systems makes it desirable for all compute resources in a center to have common access to this data without needing to copy it to each mach…
Jun, 2011
Conference Paper
NAND flash memory is a preferred storage media for various platforms ranging from embedded systems to enterprise-scale systems. Flash devices do not have any mechanical moving parts and provide low-latency access. They also require less power compared to rotating media. Unlike hard disks, flash devices use out-of-update operations and they require a garbage collection (GC)…
Jun, 2011
Conference Paper
Solid-State Drives (SSDs) offer significant performance improvements over hard disk drives (HDD) on a number of workloads. The frequency of garbage collection (GC) activity is directly correlated with the pattern, frequency, and volume of write requests, and scheduling of GC is controlled by logic internal to the SSD. SSDs can exhibit significant performance degradations w…
Jun, 2011
Conference Paper
Jun, 2011
Conference Paper
The Leadership Computing Facility (LCF) at Oak Ridge National Laboratory (ORNL) has a diverse portfolio of computational resources ranging from a petascale XT4/XT5 simulation system (Jaguar) to numerous other systems supporting development, visualization, and data analytics. In order to support vastly different I/O needs of these systems Spider, a Lustre-based center wide…
Jun, 2010
Conference Paper
This presentation provided an update on the Cray XT3 related Oak Ridge National Lab efforts.
Jun, 2010
Conference Paper
Operating system (OS) noise is defined as interference generated by the OS that prevents a compute core from performing ``useful'' work. Compute node kernel daemons, network interfaces, and other OS related services are major sources of such interference. This interference on individual compute cores can vary in duration and frequency, and can cause de-synchronization (jit…
May, 2010
Conference Paper
Journaling is a widely used technique to increase file system robustness against meta data and/or data corruptions. While the overhead of journaling can be negligible for small-scale file systems, we found that two aspects of local back-end file system journaling significantly lower the overall performance of a large-scale parallel file system such as Lustre: extra head se…
Apr, 2009
ORNL Report
Lustre was initiated and funded, almost a decade ago, by the U.S. Department of Energy (DoE) Office of Science and National Nuclear Security Administration laboratories to address the need for an open source, highly-scalable, high-performance parallel filesystem on by then present and future supercomputing platforms. Throughout the last decade, it was deployed over numerou…
Jun, 2008
Conference Paper
Data created from and used by terascale and petascale applications continues to increase, but our ability to handle and manage these files is still limited by the capabilities of the standard serialized Linux command set. This paper introduces the Center for Computational Sciences (NCCS) at Oak Ridge National Laboratory (ORNL) efforts towards providing parallelized and mor…