Re: SQL to query running transactions with subtransactions that exceeds 64

On Wed, 2021-01-06 at 11:14 +0000, Li EF Zhang wrote:
> When I restart secondary node, it reported
> "DEBUG: recovery snapshot waiting for non-overflowed snapshot or until oldest active xid on standby is at least 4739126 (now 1422751)
> CONTEXT: WAL redo at 4/741941F8 for Standby/RUNNING_XACTS: nextXid 5137417 latestCompletedXid 5137409 oldestRunningXid 1422751; 17 xacts: 2716862 2721890 4665244 2495592 2289138 5137416 2288820
> 2287653 1422751 4280517 2288510 2287620 3297674 1757103 5137219 3320989 2259670; subxid ovf"
> I want to find the oldest running transaction(1422751) using the following SQL.
> But it showed that there was no transactions that running more than 5 minutes.
> How can I find the oldest running transaction?
>
> SELECT
> pid,
> now() - pg_stat_activity.query_start AS duration,
> query,
> state
> FROM pg_stat_activity
> WHERE (now() - pg_stat_activity.query_start) > interval '5 minutes';

Use xact_start rather than query_start.

Yours,
Laurenz Albe
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