Can someone explains why this code only runs under one CONCURRENT thread.

perl -Mthreads -Mbignum -le '$_->join foreach map async { 2**859433-1 } , 1..2'

Process/threads listing 

root@blackjack:/usr/bin# ps -efL | grep perl
    root 10694  8844     1     1   0 10:32:34 pts/1       0:00 grep pe
+rl
     usr 10679  9335     1     1   3 10:32:28 pts/2       0:06 perl -M
+threads -Mbignum -cle $_->join foreach map async { 2**859433-1 } , 1.
+.2

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But by only changing the subroutine this runs across 3 CONCURRENT threads.

perl -Mthreads -Mbignum -le '$_->join foreach map async { while ($i++ < 2) {$j++; $j *= 1.1 for (1..9999)} }, 1..2'

Process/threads listing 

root@blackjack:/usr/bin# ps -efL | grep perl
    root 10757  8844     1     1   0 10:32:46 pts/1       0:00 grep pe
+rl
     usr 10755  9335     1     3   0 10:32:44 pts/2       0:00 perl -M
+threads -Mbignum -le $_->join foreach map async { while ($i++ < 2) {$
+j++
     usr 10755  9335     2     3   1 10:32:44 pts/2       0:02 perl -M
+threads -Mbignum -le $_->join foreach map async { while ($i++ < 2) {$
+j++
     usr 10755  9335     3     3   1 10:32:44 pts/2       0:02 perl -M
+threads -Mbignum -le $_->join foreach map async { while ($i++ < 2) {$
+j++

[download]

In reply to Perl threading problem? by konnjuta

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