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Amazon ElastiCache Functionality

Amazon ElastiCache gives you access to the capabilities of a familiar Memcached compatible caching environment.

To use Amazon ElastiCache, you simply:

• Use the AWS Management Console or Amazon ElastiCache APIs to launch a Cache Cluster selecting a Cache Cluster Name, Cache Node Type and Number of Nodes that best meets your needs.
• Connect to your Cache Nodes using your favorite Memcached clients or programming language. Since Amazon ElastiCache is Memcached compatible, your code and most clients should work unmodified.
• Get detailed monitoring statistics of your Cache Nodes for no additional charge via Amazon CloudWatch (you will find these in the Amazon ElasticCache tab of the AWS Management Console).
• If at any point you need additional capacity, you can add more Cache Nodes to your Cache Cluster with a few clicks of the console or a simple API call.
• Pay only for the resources you actually consume, based on your Cache Node hours used.

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Service Highlights

Simple to Deploy – Amazon ElastiCache makes it very easy to deploy a Memcached compliant cache environment. Use the AWS Management Console or simple API calls to access the capabilities of a production-ready Cache Cluster in minutes without worrying about infrastructure provisioning, or installing and maintaining cache software.

Managed – Amazon ElastiCache automates time-consuming management tasks --such as patch management, failure detection and recovery-- allowing you to pursue higher value application development.

Compatible – With Amazon ElastiCache, you get native access to a Memcached environment. This facilitates compatibility with your existing tools and applications. In addition, Amazon ElastiCache gives you optional control over which supported Memcached version powers your Cache Cluster via Cache Engine Version Management.

Elastic – With a simple API call or a few clicks of the AWS Management Console, you can add or delete Cache Nodes to your Cache Cluster to meet your application load. Auto Discovery enables automatic discovery of Cache Nodes by ElastiCache Clients when the nodes are added to or removed from an Amazon ElastiCache Cluster.

Reliable – Amazon ElastiCache has multiple features that enhance reliability for critical production deployments, including automatic failure detection and recovery. Amazon ElastiCache runs on the same highly reliable infrastructure used by other Amazon Web Services.

Designed for use with other Amazon Web Services – Amazon ElastiCache is designed for use with other Amazon Web Services, including Amazon Relational Database Service (Amazon RDS), Amazon SimpleDB, Amazon Elastic Compute Cloud (Amazon EC2), Amazon CloudWatch, and Amazon Simple Notification Service (Amazon SNS). For example, an application running in Amazon EC2 can securely connect and experience low-latency access to an Amazon ElastiCache Cluster in the same Region. Additionally, by using Amazon CloudWatch, you can get detailed monitoring statistics of a number of metrics such as cache hits and cache misses, at no extra charge. You can also set up your application to use Amazon SNS and receive e-mail notifications for key events such as failure recovery of Amazon ElastiCache Nodes.

Secure – Amazon ElastiCache provides a number of mechanisms to secure your Cache Cluster.

• Amazon ElastiCache provides web service interfaces that allow you to configure firewall settings that control network access to your Cache Cluster.
• Amazon ElastiCache allows you to run your Cache Cluster in Amazon Virtual Private Cloud (Amazon VPC). Amazon VPC enables you to isolate your Cache Cluster by specifying the IP ranges you wish to use for your Cache Nodes, and connect to your existing applications inside Amazon VPC. To learn more about Amazon ElastiCache in VPC, refer to the Amazon ElastiCache User Guide.

Cost Effective – Amazon ElastiCache saves you the administrative cost of setting up and managing a multi-node Cache Cluster. You can scale up and scale down the number of Cache Nodes in your Cache Cluster to deliver optimum performance as your application usage pattern changes, paying only for the resources you actually consume. The on-demand pricing allows you to pay for memory/compute capacity by the hour with no long-term commitments. This makes the use of Amazon ElastiCache very cost effective and frees you from the costs and complexities of planning, purchasing, and maintaining hardware.

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Features

• Pre-configured Parameters – Amazon ElastiCache Nodes are pre-configured with a sensible set of parameters and settings appropriate for the Node Type you have selected. You can simply launch a Memcached Cluster and connect your application within minutes without additional configuration. If you desire additional control, you can achieve it via Cache Parameter Groups.

• Automatic failure detection and recovery – Amazon ElastiCache monitors the health of your Cache Clusters and automatically replaces your Cache Nodes in the event of network partitioning, host hardware or software failure. The replaced Cache Nodes are designed to have the same DNS name as the failed Cache Nodes, avoiding the need for client-side refresh of end-point lists.

• Detailed Monitoring and Metrics – Amazon ElastiCache provides detailed Amazon CloudWatch metrics for your Memcached deployments at no additional charge. You can use the AWS Management Console to view key operational metrics for your Cache Nodes, including memory/compute capacity utilization, cache hits, cache misses, and number of cache connections.

• Automatic Software Patching – Amazon ElastiCache updates the cache software powering your deployment with the latest patches. You can control when and if your Cache Clusters are patched via Cache Engine Version Management.

• Push-Button Scaling – Using a few clicks of the AWS Management Console or a simple API call, you can scale the memory resources powering your deployment in minutes by adding or deleting Cache Nodes. Auto Discovery enables automatic discovery of Cache Nodes by ElastiCache Clients when the Cache Nodes in your deployment change.

Cache Node Types

Amazon ElastiCache currently supports the following Cache Node Types:

Micro

• Micro Cache Node (cache.t1.micro): 213 MB memory, Up to 2 ECU (for short periodic bursts), 64-bit platform, Low I/O Capacity

Standard

• Small Cache Node (cache.m1.small): 1.3 GB memory, 1 ECU (1 virtual core with 1 ECU), 64-bit platform, Moderate I/O Capacity
• Medium Cache Node (cache.m1.medium): 3.35 GB memory, 2 ECU (1 virtual core with 2 ECUs), 64-bit platform, Moderate I/O Capacity
• Large Cache Node (cache.m1.large): 7.1 GB memory, 4 ECUs (2 virtual cores with 2 ECUs each), 64-bit platform, High I/O Capacity
• Extra Large Cache Node (cache.m1.xlarge): 14.6 GB of memory, 8 ECUs (4 virtual cores with 2 ECUs each), 64-bit platform, High I/O Capacity

Enhanced

• Extra Large Cache Node (cache.m3.xlarge): 14.6 GB memory, 13 ECUs (4 virtual cores with 3.25 ECUs each), 64-bit platform, Moderate I/O Capacity
• Double Extra Large Cache Node (cache.m3.2xlarge): 29.6 GB memory, 26 ECUs (8 virtual cores with 3.25 ECUs each), 64-bit platform, High I/O Capacity

High-Memory

• High-Memory Extra Large Cache Node (cache.m2.xlarge): 16.7 GB memory, 6.5 ECU (2 virtual cores with 3.25 ECUs each), 64-bit platform, High I/O Capacity
• High-Memory Double Extra Large Cache Node (cache.m2.2xlarge): 33.8 GB memory, 13 ECUs (4 virtual cores with 3.25 ECUs each), 64-bit platform, High I/O Capacity
• High-Memory Quadruple Extra Large Cache Node (cache.m2.4xlarge): 68 GB memory, 26 ECUs (8 virtual cores with 3.25 ECUs each), 64-bit platform, High I/O Capacity

High-CPU

• High-CPU Extra Large Cache Node (cache.c1.xlarge): 6.6 GB memory, 26 ECUs (8 virtual cores with 2.5 EC2 Compute Units each), 64-bit platform, High I/O Capacity

Note: Each Cache Node Type above lists the memory available to Memcached after taking System Software overhead into account.

One ECU provides the equivalent CPU capacity of a 1.0-1.2 GHz 2007 Opteron or 2007 Xeon processor.

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Pricing

Pay only for what you use. There is no minimum fee. Estimate your monthly bill using the AWS Simple Monthly Calculator.

On-Demand Cache Nodes

On-Demand Cache Nodes let you pay for cache capacity by the hour your Cache Node runs with no long-term commitments. This frees you from the costs and complexities of planning, purchasing, and maintaining hardware and transforms what are commonly large fixed costs into much smaller variable costs.

Pricing is per Cache Node-hour consumed, from the time a Cache Node is launched until it is terminated. Each partial Cache Node-hour consumed will be billed as a full hour.

Reserved Cache Nodes

With Reserved Cache Nodes, you can make a low, one-time, up-front payment for each Cache Node you wish to reserve for a 1 or 3 year term. In return, you receive a significant discount off the ongoing hourly usage rate for the Cache Node(s) you reserve. Amazon ElastiCache provides three Reserved Cache Node types (Light, Medium, and Heavy Utilization Reserved Cache Nodes) that enable you to balance the amount you pay upfront with your effective hourly price. To learn more about Reserved Cache Nodes, please visit our Reserved Cache Nodes page.

Light Utilization Reserved Cache Nodes

Medium Utilization Reserved Cache Nodes

Heavy Utilization Reserved Cache Nodes

Data Transfer

Amazon ElastiCache provides strong network level security by allowing access/data transfer only from or to the Amazon EC2 Instances you define as part of your Cache Security Groups.

• There is no charge for data transfer between Amazon EC2 and Amazon ElastiCache within the same Availability Zone.
• While standard Amazon EC2 Regional Data Transfer charges of $0.01 per GB in/out apply when transferring data between an Amazon EC2 instance and an Amazon ElastiCache Node in different Availability Zones of the same Region, you are only charged for the Data Transfer in or out of the Amazon EC2 instance. There is no Amazon ElastiCache Data Transfer charge for traffic in or out of the Amazon ElastiCache Node itself.

As part of AWS’s Free Usage Tier, new AWS customers will receive free 15 GB of data transfer out each month aggregated across all AWS services for one year.

US East (N. Virginia) US West (Northern California) US West (Oregon) EU (Ireland) Asia Pacific (Singapore) Asia Pacific (Tokyo) Asia Pacific (Sydney) South America (Sao Paulo) US West (Northern California) EU (Ireland) Asia Pacific (Singapore) Asia Pacific (Tokyo) Asia Pacific (Sydney) per Hour Red Hat Enterprise Linux per GB Currency Region Windows with SQL Standard Usage Windows with SQL Web Usage All data transfer in All data transfer in Cluster Compute Reserved Instances Cluster Compute Instances Cluster GPU Instances Cluster GPU Reserved Instances Cluster GPU Instances are not available in all regions. Cluster GPU Instances are not available in all regions. Data Transfer** Data Transfer IN Data Transfer OUT Amazon EBS Snapshots to Amazon S3 Amazon EBS Provisioned IOPS volumes Amazon EBS Standard volumes EBS-Optimized Usage First 1 GB / month High-CPU On-Demand Instances High-CPU Reserved Instances High-CPU Spot Instances High-Memory Instances High-Memory On-Demand Instances High-Memory Reserved Instances High-Memory Spot Instances High-I/O On-Demand Instances High-I/O Reserved Instances High-I/O Spot Instances Second Generation Standard Instances Second Generation Standard On-Demand Instances Second Generation Standard Reserved Instances Second Generation Standard Spot Instances Second Generation Standard Storage Large Linux/UNIX Usage Medium Medium Windows Usage Next 350 TB / month Next 524 TB / month Next 4 PB / month Greater than 5 PB / month Over 5 PB / month Next 100 TB / month Next 10 TB / month Next 40 TB / month Windows® is not currently available for Cluster Compute or Cluster GPU Instances Greater than 150 TB / month per 10,000 GET requests (when loading a snapshot) per 1,000 PUT requests (when saving a snapshot) per GB in/out per GB-month of data stored per GB-month of provisioned storage per 1 million I/O requests per provisioned IOPS-month per hour Pricing PUT, COPY, POST, or LIST Requests Reduced Redundancy Storage Small (Default) Standard Instances Standard On-Demand Instances Standard Reserved Instances Standard Spot Instances Standard Storage Micro Micro On-Demand Instances Micro Reserved Instances Micro Spot Instances Up to 10 TB / month Extra Large Double Extra Large Quadruple Extra Large Eight Extra Large 1 yr Term 3 yr Term Upfront Hourly for one Elastic IP address associated with a running instance per additional Elastic IP address associated with a running instance per hour on a pro rata basis per Elastic IP address not associated with a running instance per hour on a pro rata basis per Elastic IP address remap for the first 100 remaps per month per Elastic IP address remap for additional remaps over 100 per month Detailed Monitoring for Amazon EC2 Instances per instance-hour (or partial hour) for Detailed Monitoring at 1-minute frequency per instance per month, provided at 1-minute frequency Basic Monitoring for Amazon EC2 instances (free of charge) per instance per month, provided at 5-minute frequency Monitoring for Custom Metrics per metric per month per Elastic Load Balancer-hour (or partial hour) per GB of data processed by an Elastic Load Balancer Eight Extra Large US Standard US East (N. Virginia) US West (Oregon) Asia Pacific (Sydney) South America (Sao Paulo) Standard Storage Reduced Redundancy Storage Glacier Storage Glacier Archive and Restore Requests Glacier Data Restores Glacier Storage is not available in all regions. Delete Requests Free Data Transfer** Requests Designed for 99.999999999% Durability Designed for 99.99% Durability per GB First 1 TB / month Next 49 TB / month Next 350 TB / month Next 450 TB / month Next 500 TB / month Next 4000 TB / month Next 524 TB / month Next 4 PB / month Greater than 5 PB / month Over 5000 TB / month All data transfer in PUT, COPY, POST, or LIST Requests Pricing Data Transfer IN Data Transfer OUT All data transfer in First 1 GB / month Up to 10 TB / month Next 40 TB / month Next 100 TB / month Greater than 150 TB / month All data transfer in GET and all other Requests per  1,000 requests per 10,000 requests 1-Year Term Price Per Hour Micro Cache Node Type (On-Demand) Standard Cache Node Type (On-Demand) Enhanced Cache Node Type (On-Demand) High-Memory Cache Node Type (On-Demand) High-CPU Cache Node Type (On-Demand) Micro Small Medium Large Extra Large Double Extra Large Quadruple Extra Large Extra Large Multi-AZ Cache Node Type (On-Demand) Multi-AZ, High-Memory Cache Node Type (On-Demand) Usage Rate Standard Deployment (Reserved) Multi-AZ Deployment (Reserved) Micro Small Large Extra Large Extra Large (High Memory) Double Extra Large (High Memory) Extra Large (Enhanced) Double Extra Large (Enhanced) Quadruple Extra Large (High Memory) Extra Large (High CPU) South America (Sao Paulo) 1yr 3yr US East (N. Virginia) US West (Northern California) US West (Oregon) EU (Ireland) Asia Pacific (Singapore) Asia Pacific (Tokyo) South America (Sao Paulo) Eight Extra Large per hour per GB Upfront Hourly

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Resources

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Detailed Description

Key Use Cases

Amazon ElastiCache can be used to significantly improve latency and throughput for many read-heavy application workloads (such as social networking, gaming, media sharing and Q&A; portals) or compute-intensive workloads (such as a recommendation engine). Caching improves application performance by storing critical pieces of data in memory for low-latency access. Cached information may include the results of I/O-intensive database queries or the results of computationally-intensive calculations.

Working with Amazon ElastiCache

Amazon ElastiCache allows you to use the AWS Management Console or a simple set of web services APIs to create, delete and modify Cache Clusters. A Cache Cluster is a logical collection of Cache Nodes, each running Memcached software. You can control access and security for your Cache Cluster(s) using Cache Security Groups and tune your deployments using Cache Parameter Groups.

Easily port your existing applications

If your application already relies on Memcached, you can easily port it to take advantage of Amazon ElastiCache with the following steps:

• First, create a Cache Cluster with a Cache Node Type and a Number of Cache Nodes that match your existing configuration.
• Second, configure a Cache Security Group to allow access to your Cache Cluster from your Amazon EC2 Instances (or application servers).
• Third, get the details of the endpoints (or DNS Names) of your Cache Nodes created in the first step. You can do so by visiting the Amazon ElastiCache tab of the AWS Management Console and then navigating to the “Nodes” screen corresponding to your Cache Cluster, and clicking on the “Copy Node Endpoints” button. Alternatively, you can also use the Amazon ElastiCache DescribeCacheClusters API.
• Fourth, configure your Amazon EC2 Instances to access the Cache Cluster by updating the Memcached configuration file of your client libraries to include the endpoints retrieved in the previous step.

As with any migration process, we recommend thorough testing of your new Amazon ElastiCache deployment before completing the cut over from your current solution.

Paying for What You Use

You will be charged at the end of each month for the Amazon ElastiCache resources you consumed. Once a Cache Node is deployed, you will be charged for each hour it is running (for example, $0.095/hour for a Small Cache Node). Each Cache Node will run until termination, which occurs when you delete the Cache Node or the associated Cache Cluster. Partial hours consumed are billed as full hours.

Getting Started

You can easily get started with Amazon ElastiCache by viewing a quick demo created by AWS Evangelist Simone Brunozzi or reviewing the Getting Started Guide. Once you are ready to create your own Cache Cluster(s) and start building applications, you can use the AWS Management Console or Amazon ElastiCache APIs to launch a Cache Cluster in minutes.

By default, you are allowed to have up to a total of 20 Amazon ElastiCache Nodes per customer account. If you wish to run more Cache Nodes, please complete the ElastiCache Limit Increase Request form and we will promptly respond to your request.

Setting up redundant Cache Clusters in different Availability Zones

Amazon ElastiCache monitors the health of your Cache Nodes and replaces them in the event of network partitioning, host hardware or software failure. However, given the ephemeral nature of a cache, Cache Node replacements begin empty (also called “cold”), and depending on your workload pattern, may take some time to be re-populated with data (also called “warming up”). Additionally, the auto-replacement functionality provided by Amazon ElastiCache is restricted to a single Availability Zone. If your application is sensitive to the failure recovery or the “warm up” time of Cache Nodes, or you want enhanced fault-tolerance for Availability Zone level failures, you may wish to deploy redundant ElastiCache Clusters in different Availability Zones.

One of the ways to manage data redundancy is to have your application apply all cache writes to Cache Nodes across these Availability Zones. If one or more of your Cache Nodes in the primary Availability Zone fails, you could direct reads to the corresponding Cache Node(s) in the secondary Availability Zone while Amazon ElastiCache restores the Cache Node(s) in the primary Availability Zone.

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Intended Usage and Restrictions

Your use of this service is subject to the Amazon Web Services Customer Agreement.