Re: GIN improvements part 1: additional information

On Fri, Jan 24, 2014 at 12:50 PM, Heikki Linnakangas <hlinnakangas@vmware.com> wrote:

On 01/24/2014 10:03 AM, Alexander Korotkov wrote:

ITSM I found this bug. ginVacuumPostingTreeLeaf re-encodes only some
segments. Others are not even re-palloced. They are moved left
in dataPlaceToPageLeafRecompress by memcpy. But it's incorrect to with
memcpy, proper solution is memmove. Using memcpy platform dependently can
lead to page corruption. Another solution is to re-palloc segments in
ginVacuumPostingTreeLeaf.

Good catch. Thanks, committed, changing memcpy to memmove. Will have to switch to pallocing everything in the future, if we make leafRepackItems smarter, so that it doesn't rewrite all the segments after the first modified one.

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With best regards,
Alexander Korotkov.