Limits

Network Bandwidth#

Local network works at 1 GBit/s speed, all servers have bond connection with 2x1 GBit/s link (new ones - 10Gbit/s ), so you might expect up to 100 Mb/s transfer speed for your data in ideal conditions. Please note that real transfer rate depends on many factors (overall network or a particular server load, files size, their amount, other active users in network).

Linux Home Directory Quota#

We have running a dedicated storage server for user homes. As it has physical limits in memory, disk capacity and transfer speed, all users are constrained in their disk usage with per-user disk quota. It is limited by 150 GiB with 7 days of grace time (soft quota limit) and hard limited with 200 GiB. If you use your home storage over quota your profile will effectively fall in read only mode. Please keep your home tidy and clean, empty trash bin regularly, move all large data sets onto research volumes.

To check quota state you might need to install quota utility on your local computer (if not installed yet) with sudo apt-get install quota, or log in to any server and run as:

quota -vws --show-mntpoint --hide-device --all-nfs | grep $USER

What to do if your Linux account has fallen to read-only#

You still should be able to login into command line session. Either:

  • If you’re at your Linux desktop, switch to text mode: press Ctrl+Alt+F2
  • Or connect to one of servers via SSH or PuTTY (if in Windows)

then review contents of your home profile and clean it up to get below 150 GB

DS Research Storage Limits#

Network storage from DS has it’s own limitations as well.

If your research requires relatively small volume capacity (less then 2 Tb ), it may be requested at any moment and will be ready in few days. For larger volume (5-10 TiB) you should give a proposal. All volumes are expandable, however the maximum size of a single volume size can not exceed 10 Tb.

For better performance they also recommend to keep the number of files below 10000 in each directory. If your dataset contains more, please consider to spread files by sub-directories.