Amazon EMR Serverless is a deployment possibility for Amazon EMR that you should utilize to run open supply large information analytics frameworks akin to Apache Spark and Apache Hive with out having to configure, handle, or scale clusters and servers. EMR Serverless integrates with Amazon Internet Companies (AWS) companies throughout information storage, streaming, orchestration, monitoring, and governance to offer a complete serverless analytics answer.
On this put up, we share the highest 10 greatest practices for optimizing your EMR Serverless workloads for efficiency, value, and scalability. Whether or not you’re getting began with EMR Serverless or seeking to fine-tune current manufacturing workloads, these suggestions will show you how to construct environment friendly, cost-effective information processing pipelines. The next diagram illustrates an end-to-end EMR Serverless structure, exhibiting the way it integrates into your analytics pipelines.

1. Outline functions one time, reuse a number of occasions
EMR Serverless functions operate as cluster templates that instantiate when jobs are submitted and may course of a number of jobs with out being recreated. This design considerably reduces startup latency for recurring workloads and simplifies operational administration.
Typical workflow for EMR on EC2 transient cluster:

Typical workflow for EMR Serverless:

Functions characteristic a self-managing lifecycle that provisions sources to be obtainable when wanted with out guide intervention. They routinely provision capability when a job is submitted. For functions with out pre-initialized capability, sources are launched instantly after job completion. For functions with pre-initialized capability configured, these pre-initialized staff will cease after exceeding the configured idle timeout (quarter-hour by default). You’ll be able to alter this timeout on the utility degree utilizing AutoStopConfig configuration within the CreateApplication or UpdateApplication API. For instance, in case your jobs run each half-hour, growing the idle timeout can get rid of startup delays between executions.
Most workloads are suited to on-demand capability provisioning, which routinely scales sources based mostly in your job necessities with out incurring costs when idle. This strategy is cost-effective and appropriate for typical use instances together with extract, rework, and cargo (ETL) workloads, batch processing jobs, and situations requiring most job resiliency.
For particular workloads with strict instant-start necessities, you may optionally configure pre-initialized capability. Pre-initialized capability creates a heat pool of drivers and executors which can be able to run jobs inside seconds. Nevertheless, this efficiency benefit comes with a tradeoff of added value as a result of pre-initialized staff incur steady costs even when idle till the appliance reaches the Stopped state. Moreover, pre-initialized capability restricts jobs to a single Availability Zone, which reduces resiliency.
Pre-initialized capability ought to solely be thought of for:
- Time-sensitive jobs with sub second service degree settlement (SLA) necessities the place startup latency is unacceptable
- Interactive analytics the place consumer expertise depends upon prompt response
- Excessive-frequency manufacturing pipelines operating each jiffy
In most different instances, on-demand capability offers the very best stability of value, efficiency, and resiliency.
Past optimizing your functions’ use of sources, think about the way you set up them throughout your workloads. For manufacturing workloads, use separate functions for various enterprise domains or information sensitivity ranges. This isolation improves governance and prevents useful resource rivalry between crucial and noncritical jobs.
Choosing the proper underlying processor structure can considerably influence each efficiency and price. Graviton ARM-based processors supply vital efficiency enchancment in comparison with x86_64.
EMR Serverless routinely updates to the most recent occasion generations as they turn out to be obtainable, which suggests your functions profit from the latest {hardware} enhancements with out requiring further configuration.
To make use of Graviton with EMR Serverless, specify ARM64 with the structure parameter throughout utility creation utilizing the CreateApplication or with the UpdateApplication API for current functions:
Concerns when utilizing Graviton:
- Useful resource availability – For giant-scale workloads, think about participating along with your AWS account crew to debate capability planning for Graviton staff.
- Compatibility – Though many generally used and normal libraries are appropriate with Graviton (arm64) structure, you will have to validate that third-party packages and libraries used are appropriate.
- Migration planning – Take a strategic strategy to Graviton adoption. Construct new functions on ARM64 structure by default and migrate current workloads by a phased transition plan that minimizes disruption. This structured strategy will assist optimize value and efficiency with out compromising reliability.
- Carry out benchmarks – It’s vital to notice that precise value efficiency will fluctuate by workload. We suggest performing your individual benchmarks to gauge particular outcomes to your workload. For extra particulars, check with Obtain as much as 27% higher price-performance for Spark workloads with AWS Graviton2 on Amazon EMR Serverless.
3. Use defaults, right-size staff if wanted
Employees are used to execute the duties to your workload. Whereas EMR Serverless defaults are optimized out of the field for a majority of use instances, you might must right-size your staff to enhance processing time and optimize value effectivity. When submitting EMR Serverless jobs, it’s really helpful to outline Spark properties to configure staff, together with reminiscence dimension (in GB) and variety of cores.
EMR Serverless configures the default employee dimension of 4 vCPUs, 16 GB reminiscence, and 20 GB disk. Though this typically offers a balanced configuration for many jobs, you may need to alter the scale based mostly in your efficiency necessities. Even when configuring pre-initialized staff with particular sizing, at all times set your Spark properties at job submission. This enables your job to make use of the desired employee sizing quite than default properties when it scales past pre-initialized capability. When right-sizing your Spark workload, it’s vital to establish the vCPU:reminiscence ratio to your job. This ratio determines how a lot reminiscence you allocate per digital CPU core in your executors. Spark executors want each CPU and reminiscence to course of information successfully, and the optimum ratio varies based mostly in your workload traits.
To get began, use the next steering, then refine your configuration based mostly in your particular workload necessities.
Executor configuration
The next desk offers really helpful executor configurations based mostly on frequent workload patterns:
| Workload kind | Ratio | CPU | Reminiscence | Configuration |
|---|---|---|---|---|
| Compute intensive | 1:2 | 16 vCPU | 32 GB | spark.emr-serverless.executor.cores=16spark.emr-serverless.executor.reminiscence=32G |
| Normal function | 1:4 | 16 vCPU | 64 GB | spark.emr-serverless.executor.cores=16spark.emr-serverless.executor.reminiscence=64G |
| Reminiscence intensive | 1:8 | 16 vCPU | 108 GB | spark.emr-serverless.executor.cores=16spark.emr-serverless.executor.reminiscence=108G |
Driver configuration
The next desk offers really helpful driver configurations based mostly on frequent workload patterns:
| Workload kind | Ratio | CPU | Reminiscence | Configuration |
|---|---|---|---|---|
| Normal function | 1:4 | 4 vCPU | 16 GB | spark.emr-serverless.driver.cores=4spark.emr-serverless.driver.reminiscence=16G |
| Apache Iceberg workloads | 1:8(Giant driver for metadata lookups) | 8 vCPU | 60 GB | spark.emr-serverless.driver.cores=8spark.emr-serverless.driver.reminiscence=60G |
To additional monitor and tune your configuration, monitor your workload’s useful resource consumption utilizing Amazon CloudWatch job worker-level metrics to establish constraints. Monitor CPU utilization, reminiscence utilization, and disk utilization metrics, then use the next desk to fine-tune your configuration based mostly on noticed bottlenecks.
| Metrics noticed | Workload kind | Urged motion | |
| 1 | Excessive reminiscence (>90%), Low CPU ( | Reminiscence-bound workload | Improve vCPU:reminiscence ratio |
| 2 | Excessive CPU (>85%), low reminiscence ( | CPU-bound workload | Improve vCPU depend, preserve 1:4 ratio (For instance, if utilizing 8 vCPU, use 32 GB reminiscence) |
| 3 | Excessive storage I/O, regular CPU or reminiscence with lengthy shuffle operations | Shuffle-intensive | Allow serverless storage or shuffle-optimized disks |
| 4 | Low utilization throughout metrics | Over-provisioned | Scale back employee dimension or depend |
| 5 | Constant excessive utilization (>90%) | Below-provisioned | Scale up employee specs |
| 6 | Frequent GC pauses** | Reminiscence stress | Improve reminiscence overhead (10 –15%) |
**You’ll be able to establish frequent rubbish gather (GC) pauses utilizing the Spark UI below the Executors tab. There might be a GC time column that ought to typically be lower than 10% of activity time. Alternatively, the motive force logs may continuously comprise GC (Allocation Failure)] messages.
4. Management scaling boundary with T-shirt sizing
By default, EMR Serverless makes use of dynamic useful resource allocation (DRA), which routinely scales sources based mostly on workload demand. EMR Serverless repeatedly evaluates metrics from the job to optimize for value and velocity, eradicating the necessity so that you can estimate the precise variety of staff required.
For value optimization and predictable efficiency, you may configure an higher scaling boundary utilizing one of many following approaches:
- Setting the spark.dynamicAllocation.maxExecutors parameter on the job degree
- Setting the application-level most capability
Slightly than making an attempt to fine-tune spark.dynamicAllocation.maxExecutors to an arbitrary worth for every job, you may take into consideration setting this configuration as t-shirt sizes that characterize completely different workload profiles:
| Workload dimension | Use instances | spark.dynamicAllocation.maxExecutors |
|---|---|---|
| Small | Exploratory queries, growth | 50 |
| Medium | Common ETL jobs, reviews | 200 |
| Giant | Advanced transformations, large-scale processing | 500 |
This t-shirt sizing strategy simplifies capability planning and helps you stability efficiency with value effectivity based mostly in your workload class, quite than making an attempt to optimize every particular person job.
For EMR Serverless releases 6.10 and above, the default worth for spark.dynamicAllocation.maxExecutors is infinity, however for earlier releases, it’s 100.
EMR Serverless routinely scales staff up or down based mostly on the workload and parallelism required at each stage of the job. This computerized scaling is repeatedly evaluating metrics from the job to optimize for value and velocity, which removes the necessity so that you can estimate the variety of staff that the appliance must run your workloads.
Nevertheless, in some instances, when you’ve got a predictable workload, you may need to statically set the variety of executors. To take action, you may disable DRA and specify the variety of executors manually:
5. Provision acceptable storage for EMR Serverless jobs
Understanding your storage choices and sizing them appropriately can forestall job failures and optimize execution occasions. EMR Serverless gives a number of storage choices to deal with intermediate information throughout job execution. The storage possibility chosen will depend upon the EMR launch and use case. The storage choices obtainable in EMR Serverless are:
| Storage kind | EMR launch | Disk dimension vary | Use case | Advantages |
|---|---|---|---|---|
| Serverless Storage (really helpful) | 7.12+ | N/A (auto-scaling) | Most Spark workloads, particularly data-intensive workloads |
|
| Commonplace Disks | 7.11 and decrease | 20–200 GB per employee | Small to medium workloads processing datasets below 10 TB |
|
| Shuffle-Optimized Disks | 7.1.0+ | 20–2,000 GB per employee | Giant-scale ETL workloads processing multi-TB |
|
By matching your storage configuration to your workload traits, you’ll allow EMR Serverless jobs to run effectively and reliably at scale.
6. Multi-AZ out-of-the-box with built-in resiliency
EMR Serverless functions are multi-AZ from the beginning when pre-initialized capability isn’t enabled. This built-in failover functionality offers resilience in opposition to Availability Zone disruptions with out guide intervention. A single job will function inside a single Availability Zone to forestall cross-AZ information switch prices and subsequent jobs might be intelligently distributed throughout a number of AZs. If EMR Serverless determines that an AZ is impaired, it should submit new jobs to a wholesome AZ, enabling your workloads to proceed operating regardless of AZ impairment.
To completely profit from EMR Serverless multi-AZ performance confirm the next:
- Configure a community connection to your VPC with a number of subnets throughout Availability Zones chosen
- Keep away from pre-initialized capability which restricts functions to a single AZ
- Make sure that there are adequate IP addresses obtainable in every subnet to help the scaling of staff
Along with multi-AZ, with Amazon EMR 7.1 and better, you may allow job resiliency, which permits your jobs to be routinely retried in case errors are encountered. If there are a number of Availability Zones configured, it should even be retried in a unique AZ. You’ll be able to allow this characteristic for each batch and streaming jobs, although retry conduct differs between the 2.
Configure job resiliency by specifying a retry coverage that defines the utmost variety of retry makes an attempt. For batch jobs, the default isn’t any computerized retries (maxAttempts=1). For streaming jobs, EMR Serverless retries indefinitely with built-in thrash prevention that stops retries after 5 failed makes an attempt inside 1 hour. You’ll be able to configure this threshold between 1–10 makes an attempt. For extra data, check with Job resiliency.
Within the occasion that it’s worthwhile to cancel your job, you may specify a grace interval to permit your jobs to close down cleanly quite than the default conduct of rapid termination. This will additionally embrace customized shutdown hooks if it’s worthwhile to carry out customized cleanup actions.
By combining multi-AZ help, computerized job retries, and swish shutdown intervals, you create a strong basis for EMR Serverless workloads that may tolerate interruptions and preserve information integrity with out guide intervention.
7. Safe and lengthen connectivity with VPC integration
By default, EMR Serverless can entry AWS companies akin to Amazon Easy Storage Service (Amazon S3), AWS Glue, Amazon CloudWatch Logs, AWS Key Administration Service (AWS KMS), AWS Safety Token Service (AWS STS), Amazon DynamoDB, and AWS Secrets and techniques Supervisor. If you wish to hook up with information shops inside your VPC, akin to Amazon Redshift or Amazon Relational Database Service (Amazon RDS), you will need to configure VPC entry for the EMR Serverless utility.
When configuring VPC entry to your EMR Serverless utility, hold these key concerns in thoughts to realize optimum efficiency and price effectivity:
- Plan for adequate IP addresses – Every employee makes use of one IP deal with inside a subnet. This consists of the employees that might be launched when your job is scaling out. If there aren’t sufficient IP addresses, your job may not be capable of scale, which might end in job failure. Confirm you’ve gotten adhered to greatest practices for subnet planning for optimum efficiency.
- Arrange Gateway endpoints for Amazon S3 for functions in a personal subnets – Working EMR Serverless in a personal subnet with out VPC endpoints for Amazon S3 will route your Amazon S3 site visitors by NAT gateways, leading to further information switch costs. VPC endpoints for S3 will hold this site visitors inside your VPC, lowering prices and enhancing efficiency for Amazon S3 operations.
- Handle AWS Config prices for community interfaces – EMR Serverless generates an elastic community interface file in AWS Config for every employee, which might accumulate prices as your workloads scale. When you don’t require AWS Config monitoring for EMR Serverless community interfaces, think about using resource-based exclusions or tagging methods to filter them out whereas sustaining AWS Config protection for different sources.
For extra particulars, refer Configuring VPC entry for EMR Serverless functions.
8. Simplify job submission and dependency administration
EMR Serverless helps versatile job submission by the StartJobRun API, which accepts the complete spark-submit syntax. For runtime setting configuration, use the spark.emr-serverless.driverEnv and spark.executorEnv prefixes to set setting variables for driver and executor processes. That is notably helpful for passing delicate configuration or runtime-specific settings.
For Python functions, package deal dependencies utilizing digital environments by making a venv, packaging it as a tar.gz archive, or importing to Amazon S3 utilizing spark.archives with the suitable PYSPARK_PYTHON setting variable. This enables Python dependencies to be obtainable throughout driver and executor staff.
For improved management below excessive load, allow job concurrency and queuing (obtainable in EMR 7.0.0+) to restrict the variety of jobs that may be executed concurrently. With this characteristic, jobs submitted that exceed the concurrency restrict are queued till sources turn out to be obtainable.
You’ll be able to configure Job concurrency and queue settings utilizing the SchedulerConfiguration property utilizing the CreateApplication or UpdateApplication API.
--scheduler-configuration '{"maxConcurrentRuns": 5, "queueTimeoutMinutes": 30}'
9. Use EMR Serverless configurations to implement limits
EMR Serverless routinely scales sources based mostly on workload demand, offering optimized defaults that work effectively for many use instances with out requiring Spark configuration tuning. To handle prices successfully, you may configure useful resource limits that align along with your price range and efficiency necessities. For superior use instances, EMR Serverless additionally offers configuration choices so you may fine-tune useful resource consumption and obtain the identical effectivity as cluster-based deployments. Understanding these limits helps you stability efficiency with value effectivity to your jobs.
| Restrict kind | Objective | Tips on how to configure |
|---|---|---|
| Job-level | Management sources for particular person jobs | spark.dynamicAllocation.maxExecutors or spark.executor.cases |
| Utility-level | Restrict sources per utility or enterprise area | Set most capability when creating the appliance or whereas updating. |
| Account-level | Forestall irregular useful resource spikes throughout all functions | Auto-adjustable service quota Max concurrent vCPUs per account; request will increase through Service Quotas console |
These three layers of limits work collectively to offer versatile useful resource administration at completely different scopes. For many use instances, configuring job-level limits utilizing the t-shirt sizing strategy is adequate, whereas utility and account-level limits present further guardrails for value management.
10. Monitor with CloudWatch, Prometheus, and Grafana
Monitoring EMR Serverless workloads simplifies the method of debugging, performing value optimization, and efficiency monitoring. EMR Serverless gives three tiers of monitoring that work collectively: Amazon CloudWatch, Amazon Managed Service for Prometheus, and Amazon Managed Grafana.
- Amazon CloudWatch – CloudWatch integration is enabled by default and publishes metrics to the AWS/EMRServerless namespace. EMR Serverless sends metrics to CloudWatch each minute on the utility degree, in addition to job, worker-type, and capacity-allocation-type ranges. Utilizing CloudWatch, you may configure dashboards for enhanced observability into workloads or configure alarms to alert for job failures, scaling anomalies, and SLA breaches. Utilizing CloudWatch with EMR Serverless offers insights to your workloads so you may catch points earlier than they influence customers.
- Amazon Managed Service for Prometheus – With EMR Serverless launch 7.1+, you may allow Prometheus for detailed Spark engine metrics to push metrics to Amazon Managed Service for Prometheus. This unlocks executor-level visibility, together with reminiscence utilization, shuffle volumes, and GC stress. You should use this to establish memory-constrained executors, detect shuffle-heavy phases, and discover information skew.
- Amazon Managed Grafana – Grafana connects to each CloudWatch and Prometheus information sources, offering a single pane of glass for unified observability and correlation evaluation. This layered strategy helps you correlate infrastructure points with application-level efficiency issues.
Key metrics to trace:
- Job completion occasions and success charges
- Employee utilization and scaling occasions
- Shuffle learn/write volumes
- Reminiscence utilization patterns
For extra particulars, check with Monitor Amazon EMR Serverless staff in close to actual time utilizing Amazon CloudWatch.
Conclusion
On this put up, we shared 10 greatest practices that can assist you maximize the worth of Amazon EMR Serverless by optimizing efficiency, controlling prices, and sustaining dependable operations at scale. By specializing in utility design, right-sized workloads, and architectural decisions, you may construct information processing pipelines which can be each environment friendly and resilient.
To be taught extra, check with the Getting began with EMR Serverless information.
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