DEV Community


Discussion on: Scale from Zero to Millions of Users

anduser96 profile image
Andrei Gatej

Thanks for sharing! It was a great read.

I have a couple of questions:

Inconsistency between the cache and database can happen because data-modifying operations are not a single transaction.

I’m not very familiar with this, so why are “modifying operations” not a single transaction?

What happens when the load balancer reaches its limit? I’m assuming this has a limit of requests it can intercept at once.

Thank you!

henriavo profile image
Henri Idrovo Author

Thanks for your comment Andrei. It looks like this "single transaction" feature depends on what cache vendor you choose. I took a look at an AWS caching solution and it looks like they do offer this feature!

Some databases such as Amazon Aurora offer an integrated cache that is managed within the database engine and has built-in write-through capabilities. When the underlying data changes on the database table, the database updates its cache automatically...

You can read more about it here.

Hitting a limit or quota on load balancers is a real scenario. And it looks like all you would need to do is request a quota increase. You can read more about how to do that on AWS here.