Note: Abacus4 was retired on 05.05.2014. Further information is available here.

abacus4.zedat.fu-berlin.de (

abacus4 - front angled abacus4 - wires abacus4 - grill abacus4 - front


Nodes 8x IBM p575
Processors 8x 16 = 128 CPUs, POWER 5+ Prozessors, 1.9 GHz, dual core, 1.9MB L2 Cache, 36MB L3-Cache, Simultaneous Multi-Threading
RAM 8x 128 GB = 1 TB
Storage RAID Array, 14 TB Fibre Channel, 20 TB SATA
File System General Parallel File System (GPFS)
Operating System AIX
Network Gigabit-Ethernet - TCP/IP
Interconnect Infiniband


Various pieces of software are available on abacus4. These range from development tools such as compilers and debuggers to complete scientific packages.

Queueing System

Normally programs are run on abacus4 in batch mode. This means that a program is not started immediately, but is instead sent to a so-called queueing system. This ensures that the program is only then started when enough resources are available. More information on this topic can be found here.

File Systems

There are three file systems which differ in size, speed, and whether a backup is made of the data. More information on this topic is available here.

Working Efficiently on Abacus4

In order to work efficiently on Abacus4 a certain amount of Unix knowledge is necessary. Here you will find various hints which could help you in your work.