Hello. At Fri, 30 Mar 2018 08:31:29 +0900, Fujii Masao <masao.fu...@gmail.com> wrote in <cahgqgwhvqkdfdqtvgvkty+19cqakaydxn1etgnd3x0phbz3...@mail.gmail.com> > Hi, > > When multiple relations are deleted at the same transaction, > the files of those relations are deleted by one call to smgrdounlinkall(), > which leads to scan whole shared_buffers only one time. OTOH, > during recovery, smgrdounlink() (not smgrdounlinkall()) is called > for each file to delete, which leads to scan shared_buffers multiple times. > Obviously this can cause to increase the WAL replay time very much > especially when shared_buffers is huge. > > To alleviate this situation, I'd like to propose to change the recovery > so that it also calls smgrdounlinkall() only one time to delete multiple > relation files. Patch attached. Thought?
It is obviously a left-over of 279628a0a7. This patch applies the same change with the patch and looks fine for me. Note that FinishPreparedTransaction has the same loop over smgrdounlink. regards, -- Kyotaro Horiguchi NTT Open Source Software Center
