"вам писом или послайсить?"

[ocehb]

>perl -MBenchmark=timethese -e "timethese ($ARGV[0],\
  {'A' => sub { open F,$ARGV[1]; local $/; my $a = <F>; },\
   'B' => sub { open F,$ARGV[1]; my $a = join '',<F>; } } )" 100000 file

результаты:

> wc -l my.xml & ls -alF my.xml
      2 my.xml
-rw-rw-rw-   1 user     group      115710 Jan 19 10:40 my.xml

Benchmark: timing 100000 iterations of A, B...
         A: 84 wallclock secs (53.73 usr + 22.66 sys = 76.39 CPU) @ 1309.07/s (n=100000)
         B: 150 wallclock secs (113.45 usr + 28.98 sys = 142.44 CPU) @ 702.06/s (n=100000)

> wc -l sequencer.pm & ls -alF sequencer.pm
    926 sequencer.pm
-rw-rw-rw-   1 user     group       36706 Dec 19 08:29 sequencer.pm

Benchmark: timing 100000 iterations of A, B...
         A: 40 wallclock secs (18.08 usr + 18.14 sys = 36.22 CPU) @ 2761.06/s (n=100000)
         B: 551 wallclock secs (515.11 usr + 21.98 sys = 537.09 CPU) @ 186.19/s (n=100000)

>wc -l test & ls -alF test
      3 test
-rw-rw-rw-   1 user     group          15 Feb  9 11:03 test

Benchmark: timing 100000 iterations of A, B...
         A: 22 wallclock secs ( 3.69 usr + 15.03 sys = 18.72 CPU) @ 5342.17/s (n=100000)
         B: 21 wallclock secs ( 3.94 usr + 13.80 sys = 17.73 CPU) @ 5638.89/s (n=100000)