Volumes

A volume is a file storage that is similar to traditional physical disks (SSD and HDD) but is located in the cloud.

When you create a new Virtual Machine (VM), you may need to store data or manage information. This is where volumes come in: they provide a convenient way to maintain information within the VM. Volumes are also essential for booting Virtual Machines as they store an operating system and all files necessary for machine startup.

We use a software-defined distributed file system to store data. This system comprises a cluster of easily scalable nodes that provide storage, triple data replication, and load distribution, ensuring the high availability of volumes in our cloud infrastructure.

Boot and regular volumes

Each Virtual Machine requires a volume to boot from. This volume is called a boot (or system) volume and is created based on an OS distribution image or custom image you’ve used for VM creation.

The boot volume cannot be deleted or detached from a Virtual Machine as long as the machine exists. However, after you terminate the Virtual Machine, you can keep the boot volume and its data and then use it to create another Virtual Machine.

A regular volume is a general-purpose storage volume used to retain any non-OS data in the cloud.

Info

You can create snapshots both from the boot and regular volumes. For instructions, refer to this guide: Take a snapshot of your file system.

Available volume types

In the Gcore Customer Portal, you can create different types of volumes. For instructions on how to create a volume, check out our Create and configure volumes guide.

You can check volume availability for a specific region on our website in the Gcore Cloud calculator.

Volume	Description
High IOPS SSD	This is a high-performance SSD block storage designed for latency-sensitive transactional workloads (60 IOPS per 1 GB; 2.5 MB/s per 1 GiB). The IOPS performance limit is 9,000. The bandwidth limit is 500 MB/s.
Standard	This is a network SSD disk that provides stable and high random I/O performance, as well as high data reliability (6 IOPS per 1 GB; 0.4 MB/s per 1 GiB). The IOPS performance limit is 4,500. The bandwidth limit is 300 MB/s.
Cold (deprecated)	This is a network HDD disk suitable for less frequently accessed workloads. The maximum number of IOPS is 1,000. The bandwidth limit is 100 MB/s.
Ultra (deprecated)	This is the network block storage option recommended for non-critical data and workloads that are accessed less frequently. The maximum number of IOPS is 1,000. The bandwidth limit is 100 MB/s.
SSD Low-Latency	This is an SSD block storage designed for applications that require low-latency storage and real-time data processing. It can achieve IOPS performance of up to 5000, with an average latency of 300 µs.

Snapshots and volume resizing are not supported for SSD Low-Latency volumes.

For High IOPS SSD, and Standard volumes:

• Both volume IO (Input/Output) burst and volume throughput burst are supported.

• You get both IO and throughput credits to exceed base limits and ensure optimal performance at peak IOPS and throughput.

• Credits increase IOPS and volume throughput by 10x times for 10 minutes.

For example, your Virtual Machine has a 3 GB High IOPS SSD volume with base limits of 180 IOPS and 7.5 MB (60 IOPS x 3 GB and 2.5 MB/s x 3 GB). If the IOPS and throughput values ​​exceed these limits, you’ll get renewable resources: (60 IOPS x 3 GB + 2.5 MB/s x 3 GB = 180 IOPS + 7.5 MB) x 10 = 1800 IOPS + 75 MB/s.

Credits are restored after peak usage and load reduction. If the base limits are exceeded again, renewed credits will also be applied.