Question/Request - lambda BatchInvoke limit

[stefangomez]

I can't seem to find any documentation on the limit that AppSync imposes on how many events get passed to BatchInvoke. My questions:

1. Is the limit still 5?
2. Is there a plan to increase the limit either by default or by configuration/billing?
3. Can you please document this.

I understand that for most use cases it'll bring N+1 queries down substantially, but it's still got a (N/5)+1 problem...which can become problematic at some point.

It'll be nice to have this documented somewhere, because I'm sure there are plenty of people that want to use BatchInvoke but can't or won't without knowing this first.

I'm fine if it's 5, and will stay 5 forever, but some transparency on the actual limit and plan would be appreciated. For some, and specifically for me, it's not a blocker, but knowing helps us determine the best way to write the resolver. For example, if it's a nested relationship that queries a DB, one might decide to write that query for nested elements in the top-level resolver depending on document size/memory reqs, etc. Depending on the situation a more expensive/complex 2-query call in a resolver could be better off than a cheaper/simpler (N/5)+1 call...but we need to know what we're working with! Thanks :)

[katzeforest]

Thanks for using AppSync! To answer your questions:

1. The limit is 5.
2. There are many optimizations done internally in the service, including parallel optimizations at appropriate times depending on different conditions. We are actively looking into feature like this to benefit customers. I will +1 this feature request to the team on your behalf.
3. Thank you for the feedback and we will document it.

[fgiarritiello]

+1

[adamjq]

+1

[3nvi]

Out of curiosity, is there a public roadmap available somewhere? It would be great to know if this is something that will be coming in the near future or far down the line.

Thanks!

[markoff-s]

+1

[gjimenezv]

Complete year passed and we don't have any response, the entire internet know nothing about this topic, is there any hope?

[Ricardo1980]

You have to be more annoying (that is my experience). Use Discord and Twitter and tag aws engineers.

[LMulvey]

I've received a response on AWS Support Forums before indicating that they do not have any public roadmap, sadly. That was last year but I doubt it has changed.

[collinglass]

+1

[arpitchaudhary]

+1

[photomz]

+1

[milindkhurd]

+1

This impacts my design, query performance and explodes cost. AppSync is only good for POC's not real world applications.

[MatteoGranziera]

+1

[drwxmrrs]

+1 - would love to see this implemented. Tossing up rolling our own in Apollo until this is resolved :(

[dranes]

this is a very big issue for us too, we are hitting too many connections in our database too fast and the limit of 5 is ridiculous

[metalc0der]

We are having the same problem here. We were so excited about AppSync, but this make it impossible for us to use it. Besides, the 5 limit goes against the main purpose of BatchInvoke requests in the first place.

[sebastiansanio]

Any news about this? It's a very big issue for us too.

[nacho8]

+1

[leandrosalo]

This is so frustrating

[mutasemhidmi]

When will this be fixed? It's nearly two years, and this still hasn't changed. This is so frustrating.

[kylevillegas93]

+1 - we are planning on migrating over to REST APIs and spinning up our own Apollo GraphQL server, which is a substantial undertaking, if there is no plan to increase the limit. A simple yes or no on this issue will help us make better decisions when implementing our software.

AWS AppSync Team - your lack of follow-up on this issue and lack of transparency of your roadmap clearly goes against Amazon's leadership principle of customer obsession and rather shows a disinterest in customer feature requests. Please consider prioritizing your customers first. Thanks!

[gastonsilva]

+1

[onlybakam]

Hey all, thank you for the feedback on batching. would be great to get your feedback on this:

• do you have use cases where you need to dynamically configure the batch size for your lambda resolver (i.e.: in VTL)?
• are you using Direct Lambda resolvers (DLR)? would it be helpful to configure your DLR to batch (i.e.: no VTL)?

[sebastiansanio]

Hi Brice, thanks for the response.
I answer for our case:

• it would be good to have, but not necessary. We paginate at the query level so a fixed limit but much higher than the current one would greatly improve our solution (for example, a limit of 100).
• we are using Direct lambda resolvers, so yes, it would be helpful to be able to configure the DLR to batch without VTL.

[johansteffner]

Hi @onlybakam

We are using lambda resolvers with VTL and it would be really nice to be able to configure the batch size.

[kylevillegas93]

@onlybakam we are using DLR and it would be very useful to configure the DLR to batch more than current limit of 5.

[DrWorkhard]

@onlybakam A dynamically configured batch size would be helpful. E.g. right now we fetch new elements for our feed in batches of seven. So if we could configure your batch resolver batch size to 7 we would perfectly match our internal batch size.

[mutasemhidmi]

Any update for this?

[thdxr]

@onlybakam I'll take whatever is easier, really really need this to be a higher number

[rraat]

Don't think that a configurable limit would be a requirement. Having a batch size of 100 would suffice in many cases.
If one would need a smaller batch size the parent could return less data to solve this.

[mutasemhidmi]

Need this feature

[ndejaco2]

Hi all, this enhancement has finally been released:

https://aws.amazon.com/blogs/mobile/introducing-configurable-batching-size-for-aws-appsync-lambda-resolvers/

[yvele]

@ndejaco2 cool thank you!

Is this already supported in CloudFormation?

There is nothing in AWS::AppSync::Resolver such as maxBatchSize 🤔

I tried in the request mapping template but that doesn't work:

{
  "version": "2018-05-29",
  "operation": "BatchInvoke",
  "maxBatchSize": 50, <--------------------- Does NOT work 🤷🏻‍♂️
  "payload": {
    "context": $utils.toJson($context)
  }
}

[ndejaco2]

Yes Cloudformation is supported. The property name is MaxBatchSize and it can be set on AWS::AppSync::Resolver and AWS::AppSync::FunctionConfiguration. The official Cloudformation doc update will be out this week.

[yvele]

Thank you!