On Sat, Nov 7, 2015 at 3:54 PM, Michael Paquier wrote:
> I thought about something like that at some point by saving a minimum
> activity pointer in XLogCtl, updated each time a segment was forcibly
> switched or after inserting a checkpoint record. Then the bgwriter
> looked at if the current insert position matched this minimum activity
> pointer, skipping LogStandbySnapshot if both positions match. Does
> this match your line of thoughts?
Looking at the code, it occurred to me that the LSN position saved for
a XLOG_SWITCH record is the last position of current segment, so we
would still need to check if the current insert LSN matches the
beginning of a new segment and if the last segment was forcibly
switched by saving RecPtr of RequestXLogSwitch in XLogCtl for example.
Thoughts?
--
Michael