History
Google announced Compute Engine on June 28, 2012 at Google I/O 2012 in a limited preview mode. In April 2013, GCE was made available to customers with Gold Support Package. On February 25, 2013,Google Compute Engine Unit
Google Compute Engine Unit (GCEU), which is pronounced as GQ, is an abstraction of computing resources. According to Google, 2.75 GCEUs represent the minimum power of one logical core (a hardware hyper-thread) based on thePersistent disks
Every Google Compute Engine instance starts with a disk resource called persistent disk. Persistent disk provides the disk space for instances and contains the root filesystem from which the instance boots. Persistent disks can be used as raw block devices. By default, Google Compute Engine usesImages
An image is a persistent disk that contains the operating system and root file system that is necessary for starting an instance. An image must be selected while creating an instance or during the creation of a root persistent disk. By default, Google Compute Engine installs the root filesystem defined by the image on a root persistent disk. Google Compute Engine provides CentOS andMachine types
Google Compute Engine uses KVM as the hypervisor, and supports guest images running Linux and Microsoft Windows which are used to launch virtual machines based on the 64 bit x86 architecture. VMs boot from a persistent disk that has a root filesystem. The number of virtual CPUs, amount of memory supported by the VM is dependent on the machine type selected.Billing and discounts
Google Compute Engine offers sustained use discounts. Once an instance is run for over 25% of a billing cycle, the price starts to drop: * If an instance is used for 50% of the month, one will get a 10% discount over the on-demand prices * If an instance is used for 75% of the month, one will get a 20% discount over the on-demand prices * If an instance is used for 100% of the month, one will get a 30% discount over the on-demand pricesMachine type comparison
Google provides certain types of machine: * Standard machine: 3.75 GB of RAM per virtual CPU * High-memory machine: 6.5 GB of RAM per virtual CPU * High-CPU machine: 0.9 GB of RAM per virtual CPU * Shared machine: CPU and RAM are shared between customers * Memory-optimized machine: greater than 14 GB RAM per vCPU. The prices mentioned below are based on running standardResources
Compute Engine connects various entities called resources that will be a part of the deployment. Each resource performs a different function. When a virtual machine instance is launched, an instance resource is created that uses other resources, such as disk resources, network resources and image resources. For example, a disk resource functions as data storage for the virtual machine, similar to a physical hard drive, and a network resource helps regulate traffic to and from the instances.Image
An image resource contains an operating system and root file system necessary for starting the instance. Google maintains and provides images that are ready-to-use or users can customize an image and use that as an image of choice for creating instances. Depending on the needs, users can also apply an image to a persistent disk and use the persistent disk as the root file system.Machine type
An instance's machine type determines the number of cores, the memory, and the I/O operations supported by the instance.Disk
Persistent disks are independent of the virtual machines and outlive an instance's lifespan. All information stored on the persistent disks is encrypted before being written to physical media, and the keys are tightly controlled by Google. Each instance can attach only a limited amount of total persistent disk space (one can have up to 64 TB on most instances) and a limited number of individual persistent disks (one can attach up to 16 independent persistent disks to most instances). Regional persistent disks can be replicated between two zones in a region for higher availability.Snapshot
Persistent disk snapshots lets the users copy data from existing persistent disk and apply them to new persistent disks. This is especially useful for creating backups of the persistent disk data in cases of unexpected failures and zone maintenance events.Instance
A Google Compute Engine instance is a virtual machine running on a Linux or Microsoft Windows configuration. Users can choose to modify the instances including customizing the hardware, OS, disk, and other configuration options.Network
A network defines the address range and gateway address of all instances connected to it. It defines how instances communicate with each other, with other networks, and with the outside world. Each instance belongs to a single network and any communication between instances in different networks must be through a public IP address. A Cloud Platform Console project can contain multiple networks, and each network can have multiple instances attached to it. A network allows the user to define a gateway IP and the network range for the instances attached to that network. By default, every project is provided with a default network with preset configurations and firewall rules. Users can choose to customize the default network by adding or removing rules, or they can create new networks in that project. Generally, most users only need one network, although there can be up to five networks per project by default. A network belongs to only one project, and each instance can only belong to one network. All Compute Engine networks use the IPv4 protocol. Compute Engine currently does not support IPv6. However, Google is a major advocate of IPv6 and it is an important future direction.Address
When an instance is created, an ephemeral external IP address is automatically assigned to the instance by default. This address is attached to the instance for the life of the instance and is released once the instance has been terminated. GCE also provides mechanism to reserve and attach static IPs to the VMs. An ephemeral IP address can be promoted to a static IP address.Firewall
A firewall resource contains one or more rules that permit connections into instances. Every firewall resource is associated with one and only one network. It is not possible to associate one firewall with multiple networks. No communication is allowed into an instance unless a firewall resource permits the network traffic, even between instances on the same network.Route
Google Compute Engine offers a routing table to manage how traffic destined for a certain IP range should be routed. Similar to a physical router in the local area network, all outbound traffic is compared to the routes table and forwarded appropriately if the outbound packet matches any rules in the routes table.Regions and zones
A region refers to a geographic location of Google's infrastructure facility. Users can choose to deploy their resources in one of the available regions based on their requirement. As of June 1, 2014, Google Compute Engine is available in central US region, Western Europe and Asia East region. A zone is an isolated location within a region. Zones have high-bandwidth, low-latency network connections to other zones in the same region. In order to deploy fault-tolerant applications that have high availability, Google recommends deploying applications across multiple zones in a region. This helps protect against unexpected failures of components, up to and including a single zone. As of August 5, 2014, there are eight zones - three each in central US region and Asia East region and two zones in Western Europe region.Scope of resources
All resources within GCE belong to the global, regional, or zonal plane. Global resources are accessible from all the regions and zones. For example, images are a global resource so users can launch a VM in any region based on a global image. But an address is a regional resource that is available only to the instances launched in one of the zones within the same region. Instances are launched in a specific zone that requires the zone specification as a part of all requests made to that instance. The table below summarises the scope of GCE resources:Features
Billing and pricing model
Google charges the VMs for a minimum of 10 minutes. At the end of 10th minute, instances are charged in 1-minute increments, rounded up to the nearest minute. Sustained usage based pricing will credit the discounts to the customers based on the monthly utilisation. Users need not pay a commitment fee upfront to get discounts on the regular, on-demand pricing.VM performance
Compute Engine VMs boot within 30 seconds which is considered to be 4-10x faster than the competition.Disk performance
The persistent disks of Compute Engine deliver higher IOPS consistently. With the cost of provisioned IOPS included within the cost of storage, users need not pay separately for the IOPS.Global scope for images and snapshots
Images and disk snapshots belong to the global scope which means they are implicitly available across all the regions and zones of Google Cloud Platform. This avoids the need for exporting and importing images and snapshots between regions.Transparent maintenance
During the scheduled maintenance of Google data center, Compute Engine can automatically migrate the VMs from one host to the other without involving any action from the users. This delivers better uptime to applications.References
External links
* * {{Cloud computing Cloud computing Cloud computing providers Cloud infrastructure Cloud platforms Compute Engine Web services Internet properties established in 2012