Set the metapage's pd_lower correctly in brin, gin, and spgist indexes. Previously, these index types left the pd_lower field set to the default SizeOfPageHeaderData, which is really a lie because it ought to point past whatever space is being used for metadata. The coding accidentally failed to fail because we never told xlog.c that the metapage is of standard format --- but that's not very good, because it impedes WAL consistency checking, and in some cases prevents compression of full-page images.
To fix, ensure that we set pd_lower correctly, not only when creating a metapage but whenever we write it out (these apparently redundant steps are needed to cope with pg_upgrade'd indexes that don't yet contain the right value). This allows telling xlog.c that the page is of standard format. The WAL consistency check mask functions are made to mask only if pd_lower appears valid, which I think is likely unnecessary complication, since any metapage appearing in a v11 WAL stream should contain valid pd_lower. But it doesn't cost much to be paranoid. Amit Langote, reviewed by Michael Paquier and Amit Kapila Discussion: https://postgr.es/m/0d273805-0e9e-ec1a-cb84-d4da400b8...@lab.ntt.co.jp Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/81e334ce4e6d687d548e60ad8954b7dfd9e568a2 Modified Files -------------- src/backend/access/brin/brin.c | 4 ++-- src/backend/access/brin/brin_pageops.c | 10 +++++++++- src/backend/access/brin/brin_revmap.c | 15 +++++++++++++-- src/backend/access/brin/brin_xlog.c | 21 +++++++++++++++++++-- src/backend/access/gin/ginfast.c | 26 +++++++++++++++++++++++--- src/backend/access/gin/gininsert.c | 4 ++-- src/backend/access/gin/ginutil.c | 20 +++++++++++++++++++- src/backend/access/gin/ginxlog.c | 25 ++++++++++--------------- src/backend/access/spgist/spginsert.c | 4 ++-- src/backend/access/spgist/spgutils.c | 24 ++++++++++++++++++++++-- src/backend/access/spgist/spgxlog.c | 7 ++++--- 11 files changed, 125 insertions(+), 35 deletions(-) -- Sent via pgsql-committers mailing list (pgsql-committers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-committers
