int effective_multixact_freeze_max_age;
TransactionId limit;
TransactionId safeLimit;
+ MultiXactId oldestMxact;
MultiXactId mxactLimit;
MultiXactId safeMxactLimit;
Assert(mxid_freezemin >= 0);
/* compute the cutoff multi, being careful to generate a valid value */
- mxactLimit = GetOldestMultiXactId() - mxid_freezemin;
+ oldestMxact = GetOldestMultiXactId();
+ mxactLimit = oldestMxact - mxid_freezemin;
if (mxactLimit < FirstMultiXactId)
mxactLimit = FirstMultiXactId;
ereport(WARNING,
(errmsg("oldest multixact is far in the past"),
errhint("Close open transactions with multixacts soon to avoid wraparound problems.")));
- mxactLimit = safeMxactLimit;
+ /* Use the safe limit, unless an older mxact is still running */
+ if (MultiXactIdPrecedes(oldestMxact, safeMxactLimit))
+ mxactLimit = oldestMxact;
+ else
+ mxactLimit = safeMxactLimit;
}
*multiXactCutoff = mxactLimit;