Re: pg_upgrade and rsync

On 01/22/2015 09:20 PM, Bruce Momjian wrote:
> One question I have is whether hint bits are set by read-only
> transactions on standby servers.

No. See comments in MarkBufferDirtyHint:

>         /*
>          * If we need to protect hint bit updates from torn writes, WAL-log a
>          * full page image of the page. This full page image is only necessary
>          * if the hint bit update is the first change to the page since the
>          * last checkpoint.
>          *
>          * We don't check full_page_writes here because that logic is included
>          * when we call XLogInsert() since the value changes dynamically.
>          */
>         if (XLogHintBitIsNeeded() && (bufHdr->flags & BM_PERMANENT))
>         {
>             /*
>              * If we're in recovery we cannot dirty a page because of a hint.
>              * We can set the hint, just not dirty the page as a result so the
>              * hint is lost when we evict the page or shutdown.
>              *
>              * See src/backend/storage/page/README for longer discussion.
>              */
>             if (RecoveryInProgress())
>                 return;


- Heikki