The Experts below are selected from a list of 63 Experts worldwide ranked by ideXlab platform
Donald E Porter - One of the best experts on this subject based on the ideXlab platform.
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how to get more value from your file System Directory cache
Symposium on Operating Systems Principles, 2015Co-Authors: Chiache Tsai, Yang Zhan, Jayashree Reddy, Yizheng Jiao, Tao Zhang, Donald E PorterAbstract:Applications frequently request file System operations that traverse the file System Directory tree, such as opening a file or reading a file's metadata. As a result, caching file System Directory structure and metadata in memory is an important performance optimization for an OS kernel. This paper identifies several design principles that can substantially improve hit rate and reduce hit cost transparently to applications and file Systems. Specifically, our Directory cache design can look up a Directory in a constant number of hash table operations, separates finding paths from permission checking, memoizes the results of access control checks, uses signatures to accelerate lookup, and reduces miss rates through caching Directory completeness. This design can meet a range of idiosyncratic requirements imposed by POSIX, Linux Security Modules, namespaces, and mount aliases. These optimizations are a significant net improvement for real-world applications, such as improving the throughput of the Dovecot IMAP server by up to 12% and the updatedb utility by up to 29%.
John Waggoner - One of the best experts on this subject based on the ideXlab platform.
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2009 Annual Rotary Steerable System Directory
2009Co-Authors: John WaggonerAbstract:Rotary steerable System (RSS) technology for the offshore market continues to advance amid a pull-back in oil prices. In this year's survey of manufacturers and equipment Directory there are new offerings from a number of respondents.
Chiache Tsai - One of the best experts on this subject based on the ideXlab platform.
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how to get more value from your file System Directory cache
Symposium on Operating Systems Principles, 2015Co-Authors: Chiache Tsai, Yang Zhan, Jayashree Reddy, Yizheng Jiao, Tao Zhang, Donald E PorterAbstract:Applications frequently request file System operations that traverse the file System Directory tree, such as opening a file or reading a file's metadata. As a result, caching file System Directory structure and metadata in memory is an important performance optimization for an OS kernel. This paper identifies several design principles that can substantially improve hit rate and reduce hit cost transparently to applications and file Systems. Specifically, our Directory cache design can look up a Directory in a constant number of hash table operations, separates finding paths from permission checking, memoizes the results of access control checks, uses signatures to accelerate lookup, and reduces miss rates through caching Directory completeness. This design can meet a range of idiosyncratic requirements imposed by POSIX, Linux Security Modules, namespaces, and mount aliases. These optimizations are a significant net improvement for real-world applications, such as improving the throughput of the Dovecot IMAP server by up to 12% and the updatedb utility by up to 29%.
Frank Hartley - One of the best experts on this subject based on the ideXlab platform.
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2006 annual rotary steerable System Directory
2006Co-Authors: Frank HartleyAbstract:Rotary steerable drilling Systems have become mainstream and offer advantages, including the ability to drill directionally and continuously without having to stop or slow down to change direction, allowing uninterrupted drilling with continuous weight on the bit, while at the same time providing real-time log data.
Yang Zhan - One of the best experts on this subject based on the ideXlab platform.
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how to get more value from your file System Directory cache
Symposium on Operating Systems Principles, 2015Co-Authors: Chiache Tsai, Yang Zhan, Jayashree Reddy, Yizheng Jiao, Tao Zhang, Donald E PorterAbstract:Applications frequently request file System operations that traverse the file System Directory tree, such as opening a file or reading a file's metadata. As a result, caching file System Directory structure and metadata in memory is an important performance optimization for an OS kernel. This paper identifies several design principles that can substantially improve hit rate and reduce hit cost transparently to applications and file Systems. Specifically, our Directory cache design can look up a Directory in a constant number of hash table operations, separates finding paths from permission checking, memoizes the results of access control checks, uses signatures to accelerate lookup, and reduces miss rates through caching Directory completeness. This design can meet a range of idiosyncratic requirements imposed by POSIX, Linux Security Modules, namespaces, and mount aliases. These optimizations are a significant net improvement for real-world applications, such as improving the throughput of the Dovecot IMAP server by up to 12% and the updatedb utility by up to 29%.
