Hi,
While playing around with writing a newer allocator last week (using a
somewhat slab allocator alike architecture) I found
eval_const_expressions_mutator to be surprisingly high in profiles.
For unknown reasons the function used non chained ifs for every handled
nodeType.
Replacing the if chain with if; else if; ... resulted in a small
speedup. Replacing it with a switch() in a bigger one.
When testing with a statement containing a longer VALUES statement:
pgbench -M prepared -f stmt -T 10:
orig: 10015.28
if: 10075.48
switch: 10246.52
Thats a 2.3% increase over several runs. Other statements yielded smaller but
all positive results.
As far as I can see there currently is no point for writing the function as it
is right now. Am I missing something?
Andres
