On 2018-May-23, Tom Lane wrote: > Tiffany Thang <tiffanyth...@gmail.com> writes: > > Where do I find pg_controldata? I could not locate it on the file system. > > Hmm, should be one of the installed PG executables. > > > pg_clog/ or pg_subtrans/ or pg_multixact/offsets/ are getting larger too > > but by only a few hundreds MBs. > > This is consistent with the idea that something is holding back the > oldest-transaction horizon. (However, I'd think you'd also be having > serious problems with table bloat if that were true, so it's a bit > mystifying.) Did you check for unclosed prepared transactions?
Another option is that you have a standby server with hot_standby_feedback enabled, and an open transaction there. I'm not sure to what extent it is possible for that to cause multixact problems, but it wouldn't hurt to check. -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
