On Mon, Mar 3, 2025 at 3:18 PM Fujii Masao <masao.fu...@oss.nttdata.com> wrote: > > On 2025/03/03 16:35, Jakub Wartak wrote: > > Hi Amit, > > > > On Mon, Mar 3, 2025 at 6:26 AM Amit Kapila <amit.kapil...@gmail.com> wrote: > > [..] > > > > OK, sure. > > > >> How about something like: "Note that if the clock on standby is moved > >> ahead or backward, the feedback message may not be sent at the > >> required interval. This can lead to prolonged risk of not removing > >> dead rows on primary for extended periods as the feedback mechanism is > >> based on timestamp." > > > > Sure thing. I've just added '(..) In the extreme cases this can..' as > > it is pretty rare to hit it. Patch attached. > > When the clock moves forward or backward, couldn't it affect > not only the standby but also the primary? I’m wondering > because TimestampDifferenceExceeds() seems to be used > in several places in addition to hot standby feedback. >
Right, it could impact other places as well, like background WAL flush being delayed. So, what should we do about this? Shall we leave this as is, make a general statement, find all cases and make a note about them in docs, do it for the important ones where the impact is more, or something else? -- With Regards, Amit Kapila.
