On Thu, Jan 13, 2011 at 10:43 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> I whipped up the attached patch tonight.
>
> This appears to remove the BM_JUST_DIRTIED logic. Please explain why
> that's not completely broken. Even if it isn't completely broken,
> it would seem better to do something like that as a separate patch.
Well, the only point of BM_JUST_DIRTIED is to detect whether BM_DIRTY
has been set while a buffer write is in progress. With this patch,
only BM_HINT_BITS can be set while the buffer write is in progress;
BM_DIRTY cannot. Perhaps one could make the argument that this would
be a good cleanup anyway: in the unpatched code, BM_DIRTY can only be
set while a buffer I/O is in progress if it is set due to a hint-bit
update, and then we don't really care if the update gets lost.
Although that seems a bit confusing...
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company
