> It's not in C89 but look up "alloca". I know about alloca...
> We don't use it anywhere in postgres currently so it's kind of unlikely we > would start now. :-( >> Obviously this is a bad plan if x can be a big number because you >> might crash your stack, but suppose we know that's not an issue? It >> seems a shame to have to do palloc/pfree in a situation like this. > > palloc really isn't that expensive, unless you're allocating tons of tiny > objects or you're in a tight loop it's not worth worrying about. Yeah... but... It really depends on what you compare it to. It's cheap compared to 99% of the functions in the code base - perhaps so. But it's darn expensive compared to moving the stack pointer. I have seen profiles for PostgreSQL and other systems where memory management is a sizable percentage of the CPU time, so it is not silly to worry about economizing. ...Robert -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
