# Storage Performance

You can chooose from the following Block Storage elements:

* [<mark style="color:blue;">**Hard Disk Drives (HDD)**</mark>](#hdd-storage)**:** Traditional hard disk drives for storing data that may not require high performance. Suitable for backups, archives, and cold storage.
* [<mark style="color:blue;">**Solid-State Drives (SSD)**</mark>](#ssd-storage)**:** High-performance solid-state drives for storing data that requires low latency and high throughput. Suitable for databases, virtual machines, and applications.

## Performance attributes

The following attributes are used to determine the storage performance:

* **Read/write speed, sequential:** The `read/write` speed for large blocks of data stored in a continuous sequence on the disk.
* **Read/write speed, full random:** The `read/write` speed for large blocks of data that is stored non-sequentially on the disk.
  * **Regular:** The predictable performance of the storage device when handling random read or write operations.
  * **Burst:** The short-term peak performance of the storage device when handling random read or write operations.
* **Read speed, full random:** The `read` speed for large blocks of data stored non-sequentially on the disk.
* **Write speed, full random:** The `write` speed for large blocks of data stored non-sequentially on the disk.

## HDD storage

The following performance and configurations apply per HDD volume. The performance of HDD storage is static and independent of its [<mark style="color:blue;">volume size</mark>](#hdd-storage-volume).

|         **Storage Performance**        |        **HDD Storage**        |
| :------------------------------------: | :---------------------------: |
|      Read/write speed, sequential      |  200 Mb/s at 1 MB block size  |
| Read/write speed, full random, regular | 1,100 IOPS at 4 kB block size |
|  Read/write speed, full random, burst  | 2,500 IOPS at 4 kB block size |

### HDD storage volume

The following HDD storage volume value applies.

|    **Storage Volume**   | **HDD Storage** |
| :---------------------: | :-------------: |
| Minimum size per volume |       1 GB      |
| Maximum size per volume |       4 TB      |

Larger volumes can be made available on request. For more information, contact [<mark style="color:blue;">IONOS Cloud Support</mark>](https://docs.ionos.com/support/general-information/contact-information).

## SSD storage

The SSD storage are available in two performance classes:

* **SSD Premium**
* **SSD Standard**

The following performance and configurations apply per **SSD Premium** and **SSD Standard**.

|    **Storage Performance**   |          **SSD Premium**          |          **SSD Standard**          |
| :--------------------------: | :-------------------------------: | :--------------------------------: |
| Read/write speed, sequential |  1 Mb/s pro GB at 1 MB block size | 0,5 Mb/s pro GB at 1 MB block size |
|    Read speed, full random   | 75 IOPS per GB at 4 KB block size |  40 IOPS per GB at 4 KB block size |
|   Write speed, full random   | 50 IOPS per GB at 4 KB block size |  30 IOPS per GB at 4 KB block size |

### SSD storage volume

The following SSD storage volume value applies.

|          **Storage Volume**          |                            **SSD Premium**                           |                           **SSD Standard**                           |
| :----------------------------------: | :------------------------------------------------------------------: | :------------------------------------------------------------------: |
|        Minimum size per volume       |                                 1 GB                                 |                                 1 GB                                 |
|        Maximum size per volume       |                                 4 TB                                 |                                 4 TB                                 |
| Maximum Read/write speed, sequential |                600 Mb/s per volume at 1 MB block size                |                300 Mb/s per volume at 1 MB block size                |
|    Maximum Read speed, full random   | 45,000 IOPS at 4 KB block size and min. 4 Cores, 4 GB RAM per volume | 24,000 IOPS at 4 KB block size and min. 2 Cores, 2 GB RAM per volume |
|   Maximum Write speed, full random   | 30,000 IOPS at 4 KB block size and min. 4 Cores, 4 GB RAM per volume | 18,000 IOPS at 4 KB block size and min. 2 Cores, 2 GB RAM per volume |

Larger volumes can be made available on request. For more information, contact [<mark style="color:blue;">IONOS Cloud Support</mark>](https://docs.ionos.com/support/general-information/contact-information).

### Recommendations

* The [<mark style="color:blue;">SSD storage</mark>](#ssd-storage) performance is directly related to the [<mark style="color:blue;">SSD storage volume</mark>](#ssd-storage-volume) size. To get the full benefits of high-speed SSDs, we recommend booking SSD storage units of at least 100 GB.
* You can use smaller volumes for your [<mark style="color:blue;">VDC</mark>](https://docs.ionos.com/support/general-information/glossary-of-terms#vdc), but performance will be suboptimal, compared to that of the larger units.
* When storage units are configured in the DCD, expected performance is predicted based on the volume size. For storage volumes of more than 600 GB, the performance is capped at the maximum as specified in the [<mark style="color:blue;">SSD storage volume</mark>](#ssd-storage-volume).
