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Ebb and Thin are both web servers that interface with Rack, a web server interface for Ruby.

[edit] Development

Ebb is written in C. Thin is a mixture of C and Ruby.

Since both have parsers written in C and both interface with Rack, the biggest difference comes from event handling. Thin uses EventMachine as its event handler, while Ebb does everything in C.

EventMachine is a Ruby library and is thus slower, but easier to work with.

[edit] Performance

Ebb is nearly twice as fast as Thin on raw performance. [1]

[edit] Stability

Both Ebb and Thin have yet to reach version 1.0. Thin has been reported to be working very well on production server. Ebb 0.4.0 is latest and has fixed memory footprint issue. Ebb version 0.3.0), has serious memory footprint problems and should not be used.