AWS Lambda Support
AWS Lambda concurrency and throttling fixes.
When Lambda runs out of concurrency, requests fail with 429 errors or pile up in queues. The fix is not always a higher limit: sometimes you need to protect a database, smooth a burst or stop one noisy function from starving the rest.
When You Need This
The situations where this work pays for itself.
Signs it is time
- You see Throttles in CloudWatch or TooManyRequestsException in logs
- One function consuming concurrency starves others
- A Lambda burst overwhelms your database or a partner API
- SQS-triggered functions scale faster than downstream can cope
- Asynchronous events are delayed or dropped during spikes
What you get
- A concurrency map of your functions and dependencies
- Reserved, provisioned and queue settings in infrastructure as code
- Alarms for throttles, queue age and concurrency utilization
- A tested plan for traffic spikes
How we do it
A clear, safe process you can follow along with.
1. Confirm what is being throttled
We separate account-level, function-level and event-source throttling using Throttles, ConcurrentExecutions and queue metrics.
2. Map concurrency to dependencies
We calculate how many parallel executions each downstream system can safely take.
3. Set reserved concurrency
Reserved concurrency guarantees capacity for critical functions and caps others so they cannot consume the whole account pool.
4. Smooth bursts with queues
We put SQS in front of bursty producers and use the event source mapping's maximum concurrency setting to control parallelism.
5. Handle failures properly
We configure retries, dead-letter queues and destinations so throttled asynchronous events are not lost.
6. Request limit increases when justified
When real demand exceeds the account limit, we prepare the Service Quotas request with usage evidence.
Mistakes we help you avoid
Common ways this goes wrong, and what we do instead.
Raising limits and moving the bottleneck
Unlimited Lambda scale can overload a database. We cap concurrency to what dependencies handle.
Reserving too much
Reserved concurrency is subtracted from the shared pool. We size it to leave room for everything else.
Dropping asynchronous events
Without a DLQ or destination, failed events vanish. We add them.
Frequently Asked Questions
What is the difference between reserved and provisioned concurrency?
Reserved concurrency guarantees and limits capacity and costs nothing extra. Provisioned concurrency keeps environments initialized for low latency and is billed while enabled.
How fast does Lambda scale?
Each function can add up to 1,000 concurrent executions every 10 seconds until it reaches the account limit, so very sharp spikes can still see throttling.
Why are my SQS-triggered Lambdas throttled?
The event source can scale up faster than the function or account limit allows. Setting maximum concurrency on the mapping and reserving capacity prevents contention.
Want Help With AWS Lambda concurrency and throttling fixes?
Schedule an appointment. Tell us about your environment and we will outline the safest, highest-value approach.
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