Re: GIN logging GIN_SEGMENT_UNMODIFIED actions?

Fujii Masao <masao(dot)fujii(at)gmail(dot)com> writes:
> ISTM that the cause of this issue is that gin_desc() uses XLogRecGetData() to
> extract ginxlogVacuumDataLeafPage data from XLOG_GIN_VACUUM_DATA_LEAF_PAGE
> record. Since it's registered by XLogRegisterBufData() in
> ginVacuumPostingTreeLeaf(),
> XLogRecGetBlockData() should be used, instead. Patch attached. Thought?

I think we probably have more issues than that. See for example
https://www.postgresql.org/message-id/flat/20160826072658.15676.7628%40wrigleys.postgresql.org

which clearly shows that the replay logic is seeing something wrong too:

2016-08-26 06:01:50 UTC FATAL: unexpected GIN leaf action: 0
2016-08-26 06:01:50 UTC CONTEXT: xlog redo Insert item, node:
1663/16387/33108 blkno: 6622 isdata: T isleaf: T 3 segments: 2 (add 0 items)
0 unknown action 0 ???

If it were just a matter of gin_desc() being wrong, we'd not have
gotten such a failure. (Which is not to say that gin_desc() isn't
wrong; it may well be.)

regards, tom lane