Note: All computers on this page except for Vortex have been decommissioned in April 2008. All data/files have been copied to tornado:/data0/username/cluster_files if your tornado account is still active. Otherwise, your files can be found in /data2/clusters_files. Computing Resources Available to the Group Updated on 11/1/2005. Several workstations are available specific to this group and related projects. They are cirrus, stratus, twister, front, gust and vortex.caps.ou.edu. These workstations are managed by Ming Xue and Scott Hill (sdhill@ou.edu). Cirrus is a HP/Compaq Alaph workstation running Tru64
Unix V5.0 operating system, similar to that of the Lemieux.psc.edu.
Cirrus has 4GB memory shared to by two 677mhz alpha processors, and
a total of about 200GB fast SCSI disks. The Spenbench floating point
rating (see http://www.specbench.org/cpu2000/results/cfp2000.html) of
each processor is 582. Cirrus does not support MPI, but supports shared-memory parallel via compiler kf90. makearps -p arps on cirrus invokes this parallel compiler. The parallel efficiency or speed up of ARPS using kf90 is not very good, however - you will make more efficient use of cirrus running two separate single processor jobs than running a single 2-cpu job. The native binary data byte order on cirrus is little endian, different from that of SGI (e.g. paige), Sun (e.g., Rossby of SOM), or IBM (Sooner), but the same as Intel PCs running either Linux or Windows (Boomer, stratus, front etc.). Fortran programs can be forced to read and write big endian binrary data, however, by including -convert big_endian option for f90 compiler. Another way of achieving cross-platform data compatability is to use data formats such HDF, which is fully supported by later versions of ARPS 5.0. Please also note that ARPS GRIB history files are not portable between Cirrus and other platforms. The Fortran 90 compiler version is 5.0-705, which is over 4 years old. We have seen this compiler producing wrong codes at high optimization levels so if you see very strange behavior of your code, try lower optimization level before wasting two weeks trying to debug your correct code. Trying your code on a different platform is also advised. On cirrus, /home and /usr3 are currently available for general use, and they are mounted as /cirhome and /cirusr3 on other machines). Other mounted disks are also accessible on cirrus. Paige disks /scratch and /work are accessible from cirrus. If it's your first time using cirrus, look into ~mxue/.cshrc for the definition of commands paths and other environmental variables. It's generally okay to copy my .cshrc ahd .alias into your home directory. /home, /usr1, /usr2 and /usr3 are backed up daily at night. Cirrus has a regular (fast) ethernet connection to other machines so avoid reading/writing large data sets on cross-mounted disks (e.g., /twihome on cirrus or /cirhome on twister) when you can. Stratus, twister and front are three dual-processor Xeon workstations (Dell 530) running Enterprise Redhat Linux version 4.0. Gust is a single Pentium-4 processor machine running the same Linux OS. Vortex is a dual-processor AMD Opteron server running 64-bit Redhat Enterprise Linux 3.0 for AMD. The configurations for them are: Twister: 1.7Ghz CPUs with 256K L2 cache and 1GB memory Front processor speed is up to twice that of cirrus, although the linux machines have signifiant penalty when more than one large memory jobs are running, due to their relatively low memory bandwidth. The specbench ratings for twister, stratus, front, gust and vortexc processors are, respectively, 672, 734, 825, 1285, and 1500. All Linux machines have Intel f90 compiler (ifort or ifc) version 9.0) (see ~mxue/.cshrc for the correct path and environmental variables you need to set to use this version). They also have Portland Group's pgf90 Version 4.0-1 (version 5.0 on Gust) compilers installed. pgf90 is less bugy than ifc but produces slower codes. makearps uses ifc as the default and its -f pgf90 invokes pgf90 compiler. Vortex has 64bit pgf90 that is capable of addressing more than 4gb memory so it's suitable for large memory jobs. Copy setups in vortex:/home/mxue/.cshrc. 64bit versio of ifort 9.0 is also available but it produces slower code because of the lack of processor specific optimization. Check the latest official makearps for the necessary compiler and library path settings to compile arps programs on Vortex. Stratus, Twister and Front, Gust and Vortex are linked together via a gigabit local area network. The disks on these these machines are cross-mounted via this network. Disk partitions /data and /data1 are reserved for common data storage (IHOP forecast input and output data). /data resides on a RAID5 disk array on Stratus - it's much more reliable than single disks. /data1 on Gust, however, has a probability of failure that's twice that of single disks because it's made of two stripped single disks - failure of one of the disks will cause loss of data on both disks. Neither /data and /data1 are regularly backed up. Twister has /twiusr1, /twiusr2 and /twiusr3 single disk filesystems, /twiusr1 and /twiusr3 are backed up daily, but /twiusr2 is NOT backed up. /froraid1 on front is an RAID 5 disk array available for general use. It is not backuped however. Currently, /twiusr1, /froraid1 and /vorraid1 as well as /home of each machine are available for general use. /vorraid1 has 1590GB of space. The home directories of all machines are cross-mounted (e.g., twister home as /twihome other other machines) and cirrus, twister, front and stratus /home are backed up daily. If you need more disk space, do not hesitate to ask. The byte order of native binary data on Linux machines is little endian, the same as Cirrus. Compiler switches are available with pgf90 (-byteswapio) and ifort (-convert big endian) to force big endian I/O so that the data is compatible with SGI and Sun machines. makearps defaults to big endian I/O.
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