Re: -1/0 virtualtransaction

On Mon, 2021-04-26 at 17:45 -0400, Mike Beachy wrote:
> Does anyone have any pointers on what a virtualtransaction of '-1/0' means?
> 
> I'm using SSI and an example is 
> 
>  locktype | database | relation |  page   | tuple | virtualxid | transactionid | classid | objid | objsubid |
virtualtransaction| pid |    mode    | granted | fastpath
 
>
----------+----------+----------+---------+-------+------------+---------------+---------+-------+----------+--------------------+-----+------------+---------+----------
>  page     |    16384 |   468238 |   19216 |       |            |               |         |       |          | -1/0
          |     | SIReadLock | t       | f
 
> 
>  This is incredibly hard to search for. 
> 
> I see these for page, tuple and (perhaps a clue?) one relation, and I'm seeing the page and tuple locks accumulate
overtime.
 
>  Eventually this results in an "out of shared memory" error.

Not sure, but do you see prepared transactions in "pg_prepared_xacts"?

Yours,
Laurenz Albe
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