Goal of Linux Doors (ldoor) project is to implement Solaris doors API under Linux. Doors are fast intra-machine RPC interface. Implementation consists of kernel part (written as device driver) and user-level library emulating Solaris calls.
One importartant feature of this implementation is that door invocation doesn't require creation of new thread (or taking thread from preallocated pool). In stead, address space of caller is just replaced with address space of door server. This should give performance improvement with large number of callers.
Currently there is implementation for 2.4.1 kernel.
Documentation: Original DocBook SGML DVI HTML tar ball PDF Postscript RTF
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