In-kernel web server
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An in-kernel web server is an unlimited HTTP server that runs in kernel space or equivalent. It is also known as "accelerator".
Contents
β’ Benefits
β’ Drawbacks
β’ Implementations
β’ See also
β’ References
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Benefits
β’ Performance: the path taken by data from a source device (i.e. a disk) to a destination device (i.e. a NIC). Proper asynchronous zero-copy interfaces would make this available from user-space.
β’ Scalability: with respect to number of simultaneous clients. Event notification of comparable scalability seems unlikely in user-spaceref-11.
Drawbacks
β’ Security: Kernel processes run with unlimited privileges.
β’ Portability. Every kernel needs a specific implementation route.
β’ Reliability. Failure in the webserver may crash the OS.
Implementations
β’ HP-UX: NSAhttp (NSA is an acronym for Network Server Accelerator)
β’ Mesibo In-kernel real-time messaging server
β’ SPIN: http
β’ OpenVMS: WASD.trap
See also
References
β’ endnote-1^1 CITI_TR_00-4
β’ High-Performance Memory-Based Web Servers: Kernel and User-Space Performance. Philippe Joubert, Robert B. King, Rich Neves, Mark Russinovich, John M. Tracey. IBM. T. J. Watson Research Center