Aura

Server aura.fi.muni.cz is available to FI employees and students for longer or more complex calculations. Access to the machine is created automatically by FI and PhD students; other students only for study and research purposes at the request of the supervisor of the bachelor or diploma thesis, etc.

Way of work

At present, we are not considering introducing a queue system for long-term tasks. Suffice it to run long-running processes with reduced priority (in the range of 10-19, 19 is the lowest). Long-term processes are those that run for more than an hour. To do this, for example, use the command nice ./váš_program . Additionally, you can restrict the program to use only certain processors with the command taskset . Example of starting with a minimum priority on the 11th to 15th processor:

nice -n 19 taskset -c 10-14 ./váš_program

You can use the command to change the priority of an already running process renice that can be applied to threads, processes, or process groups (see the command page for the command). However, it should be kept in mind that a process can run in multiple threads, and changing the priority for a single process can change the priority of only one thread. Listing all threads of my processes, including priority, can be obtained, for example, by the following command:

ps x -Lo pgid,pid,tid,user,nice,tty,time,args

You can perform short-term processes or interactive debugging of your programs with normal priority.

If your process does not adhere to the priority constraint and uses a large amount of computing power, the lowest priority will be set to avoid restricting other users to all your processes 19 . You may be temporarily blocked from your faculty account for repeated or more serious violations of this policy.

Disk capacity

Directories are available for temporary data that should be quickly locally available /tmp and /var/tmp on a fast RAID-10 volume. To use this space, store your data in the directory with your login. Data that is not accessed ( atime ), are automatically lubricated, u /tmp at the age of several days, u /var/tmp in a matter of months (see the file for exact settings) /etc/tmpfiles.d/tmp.conf ).

Hardware configuration

Server Aura now runs on the HP DL980 G7 platform in the configuration:

• 8 eight-core 64-bit Intel Xeon X7560 2.26 GHz processors ( 64 cores in total).
• 448 GiB DDR3 RAM
• Gigabit Ethernet connection
• 8 drives with 300GB capacity, 10k RPM, connected in RAID-10, ie 1.2 TB of logical capacity