Concerns about large group

[Hello World]

Hi, got a project that need to create groups of up to 5 ~ 10k people.

I've read FQA What is the difference between a group topic and a channel?

Seems channel would be a good choice.

Questions:

0. Can I increase the limit of group subscriber (default to 128), and how large it can be?

1. Will this group size cause performance issue or missing msg?
2. Same question as in 1, but in case only a few people in the large group is allowed to send msg, and only up to several msg per day.
3. Which database will have better performance in general? I'm concurrently considering rethinkdb with clustering.

[Gene]

On Sunday, August 8, 2021 at 9:26:28 PM UTC-7 Hello World wrote:

Hi, got a project that need to create groups of up to 5 ~ 10k people.

I've read FQA What is the difference between a group topic and a channel?

Seems channel would be a good choice.

Questions:

0. Can I increase the limit of group subscriber (default to 128),

Yes https://github.com/tinode/chat/blob/master/server/tinode.conf#L42

and how large it can be?

That depends on your usage: how many messages per second, users' attach/detach rate, permissions settings.

1. Will this group size cause performance issue

Maybe. You are welcome to do your own load testing and share the results:

https://github.com/tinode/chat/tree/master/loadtest

or missing msg?

Probably not. Clients may be disconnected though.

2. Same question as in 1, but in case only a few people in the large group is allowed to send msg, and only up to several msg per day.

Why not use the channels? Channels are designed specifically for this use case.

3. Which database will have better performance in general? I'm concurrently considering rethinkdb with clustering.

Tinode with MySQL is used about ~3 times more than with RethinkDB. MySQL is somewhat more performant too. MySQL has transactions while RethinkDB does not.