Hi,
On Thu, Jan 28, 2016 at 7:38 PM, Rahila Syed <rahilasyed90@gmail.com> wrote:
>>+ if(!scan_all)
>>+ scanned_heap_pages = scanned_heap_pages +
>>next_not_all_visible_block;
>
>>I don't want to be too much of a stickler for details here, but it
>>seems to me that this is an outright lie.
>
> Initially the scanned_heap_pages were meant to report just the scanned pages
> and skipped pages were not added to the count. Instead the skipped pages
> were deduced from number of total heap pages to be scanned to make the
> number of scanned pages eventually add up to total heap pages. As per
> comments received later total heap pages were kept constant and skipped
> pages count was added to scanned pages to make the count add up to total
> heap pages at the end of scan. That said, as suggested, scanned_heap_pages
> should be renamed to current_heap_page to report current blkno in
> lazy_scan_heap loop which will add up to total heap pages(nblocks) at the
> end of scan. And scanned_heap_pages can be reported as a separate number
> which wont contain skipped pages.
Or keep scanned_heap_pages as is and add a skipped_pages (or
skipped_heap_pages). I guess the latter would be updated not only for
all visible skipped pages but also pin skipped pages. That is,
updating its counter right after vacrelstats->pinskipped_pages++ which
there are a couple of instances of. Likewise a good (and only?) time
to update the former's counter would be right after
vacrelstats->scanned_pages++. Although, I see at least one place where
both are incremented so maybe I'm not entirely correct about the last
two sentences.
Thanks,
Amit
