On 29 May 13:14, Raimon Esteve wrote:
> Hie,
>
> when assign stock move, try_assign lock table (1). In Backend
> PostgresSQL, the lock is NOWAIT (2).
>
> When two or more users try to assign shipments at same time, "second
> user" get a nice error.
>
> Traceback is:
>
> File "/shipment.py", line 1292, in assign_try
> for m in s.inventory_moves]):
> File "/move.py", line 754, in assign_try
> Transaction().cursor.lock(cls._table)
> File "/trytond/backend/postgresql/database.py", line 359, in lock
> self.cursor.execute('LOCK "%s" IN EXCLUSIVE MODE NOWAIT' % table)
> OperationalError: could not obtain lock on relation "stock_move"
>
> Why lock() method in PSQL backend add NOWAIT option? Why not waiting
> next user request when unluck table and continue try_assin? the
> reason?
because the transaction of the waiting user is already started and so it
must be restarted to have the new committed data.
On such operational error, trytond retries 5 times per default [1] if it
is not enough for your setup you should increase it.
Or maybe you have a too long transaction keeping the lock, in such case
you must reduce the time of this transaction.
[1]
http://doc.tryton.org/3.6/trytond/doc/topics/configuration.html#retry
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Cédric Krier - B2CK SPRL
Email/Jabber: [email protected]
Tel: +32 472 54 46 59
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