[cl-ppcre-devel] scan's performance

[Igor Plekhov]

It is on sbcl-0.9.16 under Linux.

WILD> (time (scan (list :sequence :everything "abc")
                  "foobar"))
Evaluation took:
  0.017 seconds of real time
  0.006998 seconds of user run time
  0.0 seconds of system run time
  1 page fault and
  4,456,456 bytes consed.
NIL

WILD> (time (scan (list :sequence :everything "abc" :everything)
                  "foobar"))
Evaluation took:
  0.0 seconds of real time
  0.0 seconds of user run time
  0.0 seconds of system run time
  0 page faults and
  0 bytes consed.
NIL


Why so great difference?

There must be two :everything around something to the trick to
work.


PS.  Yes, I need a scan pattern generated at run time.  With a
static pattern it works incredibly fast, as usual.


--
Registered Linux User #124759