home *** CD-ROM | disk | FTP | other *** search
- flex vs. lex timings for a C tokenizer which includes keywords:
-
- Generation times:
-
- lex 83.0 secs
- flex 3.9
- flex -cfe 7.1 # uncompressed table, equivalence classes
- flex -cf 15.0 # uncompressed table, no equivalence classes
-
- Scanner object file sizes:
-
- lex 41.0K bytes
- flex 9.4K
- flex -cfe 49.6K
- flex -cf 126.5K
-
- Running times on a 28,088 line input (685K characters):
-
- lex 29.8 secs
- flex 19.3
- flex -cfe 9.0
- flex -cf 7.8
-
- The timings were made on a Sun 3/60. All times are user + system CPU time,
- and don't include hashing of identifiers.
-
- Summary:
-
- For about the same sized scanner, you get a factor of 3 in performance.
- For a 30% faster scanner, you get a scanner 1/4th the size, and it's
- generated in 1/20th the time.
- For a scanner that's 3 times larger, you get a factor of 3.8 in
- performance.
-