On 2017/06/22 16:56, Michael Paquier wrote: > On Wed, Jun 21, 2017 at 9:42 AM, Amit Langote > <langote_amit...@lab.ntt.co.jp> wrote: >> On 2017/06/20 20:37, Amit Kapila wrote: >>> On Tue, Jun 20, 2017 at 1:50 PM, Amit Langote >>> <langote_amit...@lab.ntt.co.jp> wrote: >>>> On 2017/06/19 23:31, Tom Lane wrote: >>>>> I'd suggest a rule like "if pd_lower is smaller than SizeOfPageHeaderData >>>>> then don't trust it, but assume all of the page is valid data". >>>> >>>> Actually, such a check is already in place in the tool, whose condition >>>> looks like: >>>> >>>> if (PageGetPageSize(header) == BLCKSZ && >>>> PageGetPageLayoutVersion(header) == PG_PAGE_LAYOUT_VERSION && >>>> (header->pd_flags & ~PD_VALID_FLAG_BITS) == 0 && >>>> header->pd_lower >= SizeOfPageHeaderData && >>>> header->pd_lower <= header->pd_upper && >>>> header->pd_upper <= header->pd_special && >>>> header->pd_special <= BLCKSZ && >>>> header->pd_special == MAXALIGN(header->pd_special) && ... >>>> >>>> which even GIN metapage passes, making it an eligible data page and hence >>>> for omitting the hole between pd_lower and pd_upper. >>>> >>> >>> Won't checking for GIN_META in header->pd_flags gives you what you want? >> >> GIN_META flag is not written into pd_flags but GinPageOpaqueData.flags, >> which still requires including GIN's private header. > > Did you check this patch with wal_consistency_checking? I am getting > failures so your patch does not have the masking of GIN pages > completely right: > FATAL: inconsistent page found, rel 1663/16385/28133, forknum 0, blkno 0 > CONTEXT: WAL redo at 0/39379EB8 for Gin/UPDATE_META_PAGE: > That's easily reproducible with installcheck and a standby replaying > the changes. I did not look at the code in details to see what you may > be missing here.
Oh, wasn't sure about the gin_mask() changes myself. Thanks for checking. Actually, the WAL consistency check fails even without patching gin_mask(), so the problem may be with the main patch itself. That is, the patch needs to do something else other than just teaching GinInitMetabuffer() to initialize pd_lower. Will look into that. Thanks, Amit Thanks, Amit -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
