App Scaling

Learn about scaling Apps CPU, RAM, and containers - manually or automatically

Overview

Aptible Apps are scaled at the Service level, meaning each App Service is scaled independently.

App Services can be scaled by adding more CPU/RAM (vertical scaling) or by adding more containers (horizontal). App Services can be scaled manually via the CLI or UI, automatically with the Autoscaling, or programmatically with Terraform.

Apps with more than two containers are deployed in a high-availability configuration, ensuring redundancy across different zones.

When Apps are scaled, a new set of containers will be launched to replace the existing ones for each of your App’s Services.

High-availability Apps

Apps scaled to 2 or more Containers are automatically deployed in a high-availability configuration, with Containers deployed in separate AWS Availability Zones.

Horizontal Scaling

Scale Apps horizontally by adding more Containers to a given Service. Each App Service can scale up to 32 Containers.’

Manual Horizontial Scaling

App Services can be manually scaled via the Dashboard or aptible apps:scale CLI command. Example:

  aptible apps:scale SERVICE [--container-count COUNT] 

Horizontal Autoscaling

This feature is currently in “limited release”. Contact Aptible Support to request access.

When Horizontal Autoscaling is enabled on a Service, the autoscaler evaluates Services every 5 minutes and generates scaling adjusted based on CPU usage (as percentage of total cores). Data is analyzed over a 30-minute period, with post-scaling cooldowns of 5 minutes for scaling down and 1 minute for scaling up. After any release, an additional 5-minute cooldown applies. Metrics are evaluated at the 99th percentile aggregated across all of the service containers over the past 30 minutes.

Configuration Options

Container & CPU Threshold Settings

Container & CPU Threshold Settings

• Percentile: Determines the percentile for evaluating RAM and CPU usage.
• Minimum Container Count: Sets the lowest container count to which the service can be scaled down by Autoscaler.
• Maximum Container Count: Sets the highest container count to which the service can be scaled up to by Autoscaler.
• Scale Down Threshold (CPU Usage): Specifies the percentage of the current CPU usage at which an up-scaling action is triggered.
• Scale Up Threshold (CPU Usage): Specifies the percentage of the current CPU usage at which a down-scaling action is triggered.

Time-Based Settings

The following time-based settings are available for configuration:

• Metrics Lookback Time Interval: The duration in seconds for retrieving past performance metrics.
• Post Scale Up Cooldown: The waiting period in seconds after an automated scale-up before another scaling action can be considered.
• Post Scale Down Cooldown: A defined interval in seconds to pause after an automated scale-down, before evaluating the possibility of further scaling actions.
• Post Release Cooldown: The time in seconds to wait following any general scaling operation, allowing stabilization before considering additional scaling changes.

Vertical Scaling

Scale Apps vertically by changing the size of Containers, i.e., changing their Memory Limits and CPU Limits. The available sizes are determined by the Container Profile.

Manual Vertical Scaling

App Services can be manually scaled via the Dashboard or aptible apps:scale CLI command. Example:

    aptible apps:scale SERVICE [--container-size SIZE_MB]

Vertical Autoscaling

This feature is currently in “limited release”. Contact Aptible Support to request access.

When Vertical Autoscaling is enabled on a Service, the autoscaler also evaluates services every 5 minutes and generates scaling recommendations based:

• RSS usage in GB divided by the CPU
• RSS usage levels

Data is analyzed over a 30-minute lookback period. Post-scaling cooldowns are 5 minutes for scaling down and 1 minute for scaling up. An additional 5-minute cooldown applies after a service release.Metrics are evaluated at the 99th percentile aggregated across all of the service containers over the past 30 minutes.

Configuration Options

RAM & CPU Threshold Settings

The following RAM & CPU Threshold settings are available for configuration:

• Percentile: Determines the percentile for evaluating RAM and CPU usage.
• Minimum Memory (MB): Sets the lowest memory limit to which the service can be scaled down by Autoscaler.
• Maximum Memory (MB): Defines the upper memory threshold, capping the maximum memory allocation possible through Autoscaler. If blank, the container can scale to the largest size available.
• Memory Scale Up Percentage: Specifies the percentage of the current memory limit at which the service’s memory usage triggers an up-scaling action.
• Memory Scale Down Percentage: Determines the percentage of the next lower memory limit that, when reached or exceeded by memory usage, initiates a down-scaling action.
• Memory Optimized Memory/CPU Ratio Threshold: Establishes the ratio of Memory (in GB) to CPU (in CPUs) at which values exceeding the threshold prompt a shift to an R (Memory Optimized) profile.
• Compute Optimized Memory/CPU Ratio Threshold: Sets the Memory-to-CPU ratio threshold, below which the service is transitioned to a C (Compute Optimized) profile.

Time-Based Settings

The following time-based settings are available for configuration:

• Metrics Lookback Time Interval: The duration in seconds for retrieving past performance metrics.
• Post Scale Up Cooldown: The waiting period in seconds after an automated scale-up before another scaling action can be considered.
• Post Scale Down Cooldown: A defined interval in seconds to pause after an automated scale-down, before evaluating the possibility of further scaling actions.
• Post Release Cooldown: The time in seconds to wait following any general scaling operation, allowing stabilization before considering additional scaling changes.

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FAQ

How do I scale my apps and services?

See our guide here for How to scale apps and services

How can I get access to autoscaling?

Contact Aptible Support to request access!