I've done some benchmarks for various CL implementations for my UMLisp package. I use UMLisp mostly in the context of a web-based server. Since the Unified Medical Language System database is 8GB of SQL data, queries can take seconds to minutes. So CL implementations with true multi-threading (Allegro and Lispworks) are suitable for the UMLisp web server while CMUCL and SBCL are not.
The first benchmark is concerned with loading SQL objects via CLSQL and creating CLOS objects while the second benchmarks printing using metaclass-driven formatting.
The free CL implementations which not not have true multithreading , CMUCL and SBCL, do great on this benchmark. Allegro trails significantly in the narrow-benchmark of formatting via metaclass-stored formatting data.
| Implementation | Load | Print |
| CMUCL | 4.6s | 45s |
| SBCL | 5.1s | 61s |
| Lispworks | 11.7s | 46s |
| Allegro | 13.2 | 126s |