Re: Type of wait events WalReceiverWaitStart and WalSenderWaitForWAL

On 2021/03/18 18:48, Fujii Masao wrote:
>> 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.)
>
> IMO this should be IPC because walreceiver is mainly waiting for the
> interaction with the startup process, during this wait event. Since you can
> live with IPC, probably our consensus is to use IPC?

If this is ok, I'd like to apply the attached patch at first.
This patch changes the type of WAIT_EVENT_WAL_RECEIVER_WAIT_START
from Client to IPC.

BTW, I found that recently WalrcvExit wait event was introduced.
But this name is not consistent with other events. I'm thinking that
it's better to rename it to WalReceiverExit.

Regards,

--
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION