[Chicken-janitors] #286: utc-time->seconds is abysmally slow on OS X

[Chicken Trac]

#286: utc-time->seconds is abysmally slow on OS X
---------------------------------------------+------------------------------
 Reporter:  zbigniew                         |       Owner:       
     Type:  enhancement                      |      Status:  new  
 Priority:  not urgent at all                |   Milestone:       
Component:  core libraries                   |     Version:  4.5.x
 Keywords:  utc-time->seconds slow molasses  |  
---------------------------------------------+------------------------------
 This could be an os problem but I thought I would document it for later
 use.

 Here is my test:

 {{{
 $ time csi -R posix -R srfi-1 -e '
 (time (for-each (lambda (x)
          (utc-time->seconds (vector 0 0 4 1 0 70 4 0 #f 0)))
      (iota 10000)))'
 }}}

 Here is my Linux box results (3GHz athlon X4 940):

 {{{
 0.02s CPU time, 200815 mutations, 5/57 GCs
 real    0m0.041s
 }}}

 Here is my Mac OS X 10.5 results (c2d intel processor, 2.16GHz):

 {{{
 17.789s CPU time, 0.006s GC time (major), 200815 mutations, 5/5 GCs
 (major/minor)
 real    0m54.934s
 }}}

 Overhead for vector creation in the test is about 0.05s and does not
 materially affect total time.

 Note that local-time->seconds instead doesn't have this problem though
 (again on OS X):

 {{{
 0.091s CPU time, 0.003s GC time (major), 111 mutations, 1/9 GCs
 (major/minor)
 real    0m0.123s
 }}}

 Weird!

-- 
Ticket URL: <http://www.irp.oist.jp/trac/chicken/ticket/286>
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