Re: Type of wait events WalReceiverWaitStart and WalSenderWaitForWAL - Mailing list pgsql-hackers

From Fujii Masao
Subject Re: Type of wait events WalReceiverWaitStart and WalSenderWaitForWAL
Date
Msg-id 29b2a034-80b5-d8b3-4681-a87c298a4e4a@oss.nttdata.com
Whole thread Raw
In response to Re: Type of wait events WalReceiverWaitStart and WalSenderWaitForWAL  (Fujii Masao <masao.fujii@oss.nttdata.com>)
List pgsql-hackers

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

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