Sending messages is slow in large groups

[xAbdaziz]

When I send a message in a group with 100+ members it takes 5-10 seconds to send, meanwhile in small groups & PM it's sent instantly.
I'm using the example code in godocs.

I also noticed that there's warnings spam in my console when I send a message
[Client WARN] Failed to fetch prekey for 123456789.0:15@s.whatsapp.net: invalid prekey in prekey response: prekey node doesn't contain ID tag

Can someone please tell me what should I do to fix this issue?

[mamur-rezeki]

Also looking for the solution.

[mamur-rezeki]

So I've migrate to postgresql database (SSD). Simple text message could take ± 4 seconds with 266 group participants. It is similar with SQLite database on SSD storage, take ± 6 seconds for same message and group. While SQLite on HDD is pretty slow for ± 55 seconds.

Three scenarios have tested on initial message send and secondary message if in this case they have prekey caching (or not).

I don't know if then Message node encryption is using databases to store the prekey or Identity and get it for encrypting 1 message node for every number participants. I'm running on 150Mbps network speed.

[rull05]

any solution?

[JustSoursop]

Encrypting a message for a large group is very slow. So we need to avoid it being encrypted by whatsmeow .
The current solution is limiting the participants in this list

whatsmeow/send.go

Lines 539 to 542 in 350073d

	participants, err = cli.getGroupMembers(ctx, to)
	if err != nil {
	return "", nil, fmt.Errorf("failed to get group members: %w", err)
	}

just like this :

participants = []types.JID{ownID}