I was involved in the design and implementation of new architecture for buffer cache called Global Recycle Queues(GRQ). The work involved implementation of a global prioritization of buffers in the system while allowing for distributed processing of buffers. The new design was developed from scratch and solved many of the problems in previous buffer cache subsystem. I was also involved in providing support infrastructure for read-caching mechanisms for hybrid aggregates. Previous projects in WAFL Data Ontap:• Implementation of efficient methods to distribute free buffers onto per CPU lists in order to provide easy access to free buffers for workloads.• Tracing mechanism that would guarantee data traces for a certain period of time in critical functions in WAFL.• Design and Implementation of validation framework to provide an ability to validate the data structures in buffer/free cache.• Mechanisms in buffer cache to handle speculative read aheads to aid scavenging.• Performance improvement of Data Ontap by efficiently parallelizing the code.• Worked on thread synchronization and deadlock avoidance schemes in WAFL.• Deep understanding of memory management design in Data Ontap including buffer distribution and scavenging.Publications : Co-Author in NATJ paper on Global Recycle Queue (GRQ) model Think global, Act local : A holistic buffer cache design for global ordering and distributed processing.

My primary focus/interest was in Operating systems/systems programming.

Designed and implemented a benchmarking tool for generation of datasets (up to TeraBytes of data) that would exhibit user-specified data duplication characteristics. The characteristics include the fingerprint distributions of the dataset across configurable number of buckets, inter and intra file sharing pattern, file size distribution and deduplication factor. This facilitated in analyzing WAFL dedup performance by controlled experiments.

Designed and implemented a content management system (CMS) based on Service oriented architecture (SOA). It required storing, controlling, versioning, and publishing industry-specific documentation such as news articles, operators’ manuals, technical manuals, sales guides, and marketing brochures for customers. I was also involved in the workflow module of the project. The workflow engine would interpret the user actions like saving a document and issue emails to users based on business rules. I also have the experience of integrating large scale applications. The content management system was integrated with the Liferay portal.

Conceptualized and designed an Event Categorization and Firmware Management System for Storage Area Network (SAN). The two major goals in the design were identifying the nature of events in SAN and providing a detailed description of these events to its users by categorizing the events based on our rule sets. The data collector was designed to obtain data from the events logged in different switches in SAN. Later, predefined rule sets were applied on the information obtained from this data collector to optimize SAN performance. The firmware management module contained a databasefor checking the compatibility among different components of SAN. The designed system was highly scalable as it provided a convenient interface for creating and updating the firmware database. This project was short-listed for presentation at the HP student conference 2007 held at Bangalore.