The print is buffered, so only generates a system call when the buffer is full. My template is small and the buffer size is larger than it, so I only have one system call for the entire template.

#!/usr/bin/perl

for(my $i=0;$i<4000;$i++)
{
  print $i%10;
}
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$ strace -c -e write /tmp/t20 >/tmp/out
% time     seconds  usecs/call     calls    errors syscall
------ ----------- ----------- --------- --------- ----------------
100.00    0.000034          34         1           write
------ ----------- ----------- --------- --------- ----------------
100.00    0.000034                     1           total