Re: [GENERAL] NOTIFY command impact

Thanks Tom,

Can you answer my original question too:

If I am issuing NOTIFY commands every 30 seconds (and immediately committing) and there are no listeners, will that
havea negative impact on the cluster?
 

I'm using the NOTIFY to force streaming replication to update the "pg_last_xact_replay_timestamp" on the slaves so we
canmore accurately monitor replication lag on quiet systems.
 

Thanks,
Rob

On 2/21/17, 5:03 PM, "Tom Lane" <tgl@sss.pgh.pa.us> wrote:

    Rob Brucks <rob.brucks@rackspace.com> writes:
    > If a notify is sent and then PG is immediately shut down, wouldn't PG want to save that message for processing
afterstartup?
 
    > Or is the message just discarded?
    
    NOTIFY data is not saved across a shutdown or crash.
    
    (The reason it goes into the WAL stream is so that you can have listeners
    on replication slaves, not for recovery purposes.)
    
                regards, tom lane