Re: WAL format and API changes (9.5)

Hi,

On 2014-04-04 10:48:32 +0300, Heikki Linnakangas wrote:
> But if we give the checkpointer process a free pass, running the regression
> tests with an assertion in AllocSetAlloc catches five genuine bugs:
> 
> 1. _bt_newroot
> 2. XLogFileInit
> 3. spgPageIndexMultiDelete
> 4. PageRepairFragmentation
> 5. PageIndexMultiDelete

Some of those, like PageRepairFragmentation, are somewhat bad...

> @@ -484,10 +483,11 @@ PageRepairFragmentation(Page page)
>          ((PageHeader) page)->pd_upper = pd_special;
>      }
>      else
> -    {                            /* nstorage != 0 */
> +    {
>          /* Need to compact the page the hard way */
> -        itemidbase = (itemIdSort) palloc(sizeof(itemIdSortData) * nstorage);
> -        itemidptr = itemidbase;
> +        itemIdSortData itemidbase[MaxHeapTuplesPerPage];
> +        itemIdSort    itemidptr = itemidbase;
> +

That's a fair bit of stack, and it can be called somewhat deep on the
stack via heap_page_prune_opt(). I wonder if we ought to add a
check_stack_depth() somewhere.

Thanks,

Andres Freund