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.
Thanks,
Luca
