PostgreSQL PL speed test

I tested four procedure languages for PostgreSQL 9.2: plpgsql, plperl, plpython2u, plperl and plv8 with Fibonacci numbers function. And V8 was the best!




Functions:
postgres=# \sf jsfib
CREATE OR REPLACE FUNCTION public.jsfib(a integer)
 RETURNS integer
 LANGUAGE plv8
AS $function$
function fib(n) {
return n < 2 ? n : fib(n - 1) + fib(n - 2)
}

return fib(a)
$function$

postgres=# \sf perlfib(integer)
CREATE OR REPLACE FUNCTION public.perlfib(integer)
 RETURNS integer
 LANGUAGE plperl
AS $function$
sub fib {
 my ($n) = @_;
 if ($n < 2) {
  return $n;
 }
 return fib($n - 1) + fib($n - 2);
}
return fib($_[0]);
$function$

postgres=# \sf psqlfib
CREATE OR REPLACE FUNCTION public.psqlfib(n integer)
 RETURNS integer
 LANGUAGE plpgsql
 IMMUTABLE STRICT
AS $function$
BEGIN
IF n < 2 THEN
RETURN n ;
END IF ;
RETURN psqlfib (n - 1 ) + psqlfib (n - 2 ) ;
END;
$function$

postgres=# \sf pythonfib
CREATE OR REPLACE FUNCTION public.pythonfib(a integer)
 RETURNS integer
 LANGUAGE plpython2u
AS $function$
 def fib(n):
  if n < 2:
    return n
  return fib(n - 1) + fib(n - 2)

 return fib(a)
$function$

postgres=# EXPLAIN ANALYZE SELECT n , jsfib(n) FROM generate_series ( 0 , 30 , 5 ) as n ;
Total runtime: 26.517 ms 

postgres=# EXPLAIN ANALYZE SELECT n , pythonfib(n) FROM generate_series ( 0 , 30 , 5 ) as n ; 
Total runtime: 607.102 ms

postgres=# EXPLAIN ANALYZE SELECT n , perlfib(n) FROM generate_series ( 0 , 30 , 5 ) as n ;
Total runtime: 1530.294 ms

postgres=# EXPLAIN ANALYZE SELECT n , psqlfib(n) FROM generate_series ( 0 , 30 , 5 ) as n ; 
Total runtime: 34838.510 ms