On Thu, Aug 5, 2021 at 6:27 PM Vijaykumar Jain <vijaykumarjain.github@gmail.com> wrote: > postgres/varsup.c at master · postgres/postgres (github.com) > I think, this block when it is about to assign the next xid, it does the math, and triggers an autolauncher start. > I might be wrong, I did not run a backtrace though :) > > * Check to see if it's safe to assign another XID. This protects against > * catastrophic data loss due to XID wraparound. The basic rules are: > * If we're past xidVacLimit, start trying to force autovacuum cycles. > * If we're past xidWarnLimit, start issuing warnings. > * If we're past xidStopLimit, refuse to execute transactions, unless > * we are running in single-user mode (which gives an escape hatch > * to the DBA who somehow got past the earlier defenses).
Seem reasonable as explaination, even if sounds to me xidVacLimit is 65536.