Re: [HACKERS] palloc() vs static define?

>
> in commands/cluster.c, in function cluster, we define NewIndexName as:
>
> char NewIndexName[NAMEDATALEN]; /* line 93 */
>
> in function copy_index, we define it as:
>
> char *NewIndexName; /* line 246 */
>
> And then palloc(NAMEDATALEN) before it gets used...
>
> Now, which we use doesn't much matter to me, but I would think some sort
> of consistency would be in order...or am I missing something as far as
> each are concerned? Is one method inheriently faster then another, or do
> they have about the same performance characteristics?

Uh, O, Marc is coding. :-)

cluster.c was written by a hack, and has been cleaned up over time. You
can use either method.

> char NewIndexName[NAMEDATALEN]; /* line 93 */

Allocated stack space on function entry, and releases it on function
exit.

> And then palloc(NAMEDATALEN) before it gets used...

palloc() allocates at function call time, and you have to pfree it, or
wait for transaction to pfree it. If you are starting/stopping
transactions between palloc() and pfree() you could loose the memory
unless you change to the 'cache' memory context before doing the palloc
and pfree. See other command/*.c files for examples of this.

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