Re: Type of wait events WalReceiverWaitStart and WalSenderWaitForWAL

At Wed, 17 Mar 2021 15:31:37 +0900 (JST), Kyotaro Horiguchi <horikyota(dot)ntt(at)gmail(dot)com> wrote in
> WAIT_EVENT_WAL_RECEIVER_MAIN(WalReceiverMain) is waiting for new data
> to arrive. This looks like an activity to me.
>
> WAIT_EVENT_WAL_RECEIVER_WAIT_START is waiting for waiting for starup
> process to kick me. So it may be either IPC or Activity. Since
> walreceiver hasn't sent anything to startup, so it's activity, rather
> than IPC. However, the behavior can be said that it convey a piece of
> information from startup to wal receiver so it also can be said to be
> an IPC. (That is the reason why I don't object for IPC.)
>
> 1(WAIT_EVENT_WAL_SENDER_MAIN, currently an activity) is waiting for
> something to happen on the connection to the peer
> receiver/worker. This might either be an activity or an wait_client,
> but I prefer it to be wait_client, as the same behavior of a client
> backend is categorizes as wait_client.
>
> 2 (WAIT_EVENT_WAL_SENDER_WRITE_DATA, currently a wait_client) is the
> same to 1.
>
> 3 (WAIT_EVENT_WAL_SENDER_WAIT_WAL, currently a wait_client) is the
> same to 1.

- As the result I'd prefer to categorize all of them to Activity.

Year, I don't understand what I meant:(

+ As the result I'd prefer to categorize the first two to Activity, and
+ the last three to wait_client.

regards.

--
Kyotaro Horiguchi
NTT Open Source Software Center