"I don't know the actual performance of commercial Lisps like Allegro Common Lisp and LispWorks, but I imagine it is quite good, given that they stay in busines

"I don't know the actual performance of commercial Lisps like Allegro Common Lisp and LispWorks, but I imagine it is quite good, given that they stay in business." It might be good or just OK on modern hardware. I imagine they stayed in business for their IDE's, libraries, commercial support, and decent compilers. Batteries included. Some success stories make me think performance is really good, though. http://www.lispworks.com/success-stories/netfonds-primetrader.html http://www.lispworks.com/success-stories/netfonds-primetrade... http://www.lispworks.com/success-stories/ral-siglab.html http://www.lispworks.com/success-stories/ral-siglab.html I found those while looking for one about a real-time implementation for telecom or something. Franz's success stories are mostly about doing complicated stuff easier. There was one that looked performance-critical: http://franz.com/success/customer_apps/finance/ravenpack.lhtml http://franz.com/success/customer_apps/finance/ravenpack.lht...