# System requirements

## Hardware

### OMERO.server

The system requirements for OMERO.server vary greatly depending on image size and number of users. The minimum requirements should be easily exceeded by any recently bought hardware.

An OMERO.server specification for between 25-50 users might be:

- Quad-core Intel or AMD CPU

- 8 GB RAM

- 256 GB solid-state drive space for OMERO.server distribution

- Hard drive space proportional to the image sizes expected (likely between 10 and 100 TB)

A specification for a server future-proofed for 3-4 years might be:

- Intel Xeon Gold 6426 Processor

- 32 GB DDR5-4800

- 2 x 2 TB SSD RAID1 for OS, PostgreSQL DB, scratch, log files, etc.

- 10 GbE connectivity to a separate fileshare for the OMERO binary repository

#### Storage

Hard drive space should be proportional to the image sizes expected. The drive space should permit proper locking, which is often not the case with remotely mounted shares. See the binary repository section for more information.

#### RAM

RAM is not going to scale linearly, particularly with the way the JVM works. You are probably going to hit a hard ceiling between 4 and 6 GB for JVM size (there is really not much point in having it larger anyway). With a large database and aggressive PostgreSQL caching your RAM usage could be larger. Still, even for a large deployment, it is not cost effective to use more than a few GBs of RAM for this purpose. Performance and monitoring provides information about fine-tuning the server processes’ memory usage. In summary, depending on hardware layout 16, 24 or 32 GB of RAM would be ideal for your OMERO server. If you have a separate database server more than 16 GB of RAM may not be of much benefit to you at all.

#### CPU

CPU is not something that an OMERO system is usually ever limited by. However, when it is limited, it is almost always limited by single thread performance and not by the CPU core count. A 16 system core count should be more than enough. You are not going to get a huge OMERO performance increase by, for example, throwing 24 cores at the problem; a specification with a focus on higher single thread performance is going to give you better performance.

#### Further examples

Example production server set-ups provides details on some production set-ups in use by OMERO admins, along with how many users and the amount of data they support, which you may find helpful.

### OMERO.insight and OMERO.importer

The recommended client specification is:

- Intel or AMD CPU

- 8 GB RAM

- 120 GB solid-state drive (SSD)

### Client configuration

When performing some operations the clients make use of temporary file storage and log directories. The table below indicates the default values for each directory and the environment variables for overriding their locations:

Client directory | Environment variable | Default location (UNIX) | Default location (Windows)
--- | --- | --- | ---
OMERO user directory | `OMERO_USERDIR` | `$HOME/omero` | `%HOMEPATH%\omero`
Temporary files | `OMERO_TMPDIR` | `$HOME/omero/tmp` | `%HOMEPATH%\omero\tmp`
Local sessions | `OMERO_SESSIONDIR` | `$HOME/omero/sessions` | `%HOMEPATH%\omero\sessions`
Log files |  | `$HOME/omero/log` | `%HOMEPATH%\omero\log`

Note that setting `OMERO_USERDIR` will also change the default location for the temporary files and the local sessions.

If your home directory is stored on a network, possibly NFS mounted (or similar), then these temporary files are being written and read over the network. This can slow access down.

See also

Troubleshooting performance issues with the clients

  Troubleshooting section about client performance issues on NFS

## Software

Each component of the OMERO platform has a separate set of prerequisites. Where possible, we provide tips on getting started with each of these technologies, but we can only provide free support within limits.

Package | OMERO.server | Java | Python | Ice | PostgreSQL
--- | --- | --- | --- | --- | ---
OMERO.importer | Required | Required |  |  |
OMERO.insight | Required | Required |  |  |
OMERO.server |  | Required | Required | Required | Required
OMERO.web | Required |  | Required | Required |
OMERO.py | Required for some functionality |  | Required | Required |
OMERO.cpp | Required for some functionality |  |  | Required |

For full details on which versions of these are supported for OMERO 5.6 and how we intend to update these going forward, see the Version requirements section.