At Fri, 9 Oct 2020 13:41:25 +0800, "movead...@highgo.ca" <movead...@highgo.ca> wrote in > Hello hackers, > > We know that pg_waldump can statistics size for every kind of records. When I > use > the feature I find it misses some size for XLOG_SWITCH records. When a user > does > a pg_wal_switch(), then postgres will discard the remaining size in the > current wal > segment, and the pg_waldump tool misses the discard size. > > I think it will be better if pg_waldump can show the matter, so I make a > patch > which regards the discard size as a part of XLOG_SWITCH record, it works if we > want to display the detail of wal records or the statistics, and patch > attached. > > What's your opinion?
I think that the length of the XLOG_SWITCH record is no other than 24 bytes. Just adding the padding? garbage bytes to that length doesn't seem the right thing to me. If we want pg_waldump to show that length somewhere, it could be shown at the end of that record explicitly: rmgr: XLOG len (rec/tot): 24/16776848, tx: 0, lsn: 0/02000148, prev 0/02000110, desc: SWITCH, trailing-bytes: 16776944 regards. -- Kyotaro Horiguchi NTT Open Source Software Center
