kongo is a SPARCstation-10 model 30. It has a single 36 MHz Superscalar SPARC Version 8 (sun4m) CPU (SPECint92 45.2, SPECfp92 54.0, 101.6 MIPS, 20.5 MFLOPS). There are three SCSI-2 busses in the machine running at twice the speed of normal SCSI busses (10MB/sec burst). Two gigabytes of disk space is spread over two fast SCSI busses. kongo has 64 megabytes of RAM and a 5GB 8mm backup system.
Purchase and configuration decisions for kongo were made
with the idea of it being upgraded to a multiprocessor system in the future and its role as a compute server foremost in mind. For instance, unlike most of our other server machines, kongo does not serve any filesystems to other machines, eliminating file export service overhead. The majority of disk space has been dedicated to two large spaces, each on a separate I/O bus. The first is almost half a gigabyte of swap space. The other is a 350 megabyte data space (/var/tmp).
For best performance, and to take advantage of the two fast I/O paths, we suggest that you make use of /var/tmp as a temporary space for any large binaries you have, and for your datafiles. Doing this will allow you to localize all disk activity associated with your job to kongo, while not interfering with swap activity since /var/tmp uses the second bus.
There are a couple of caveats to keep in mind though regarding /var/tmp. First, please try to keep it clean. When you are finished with a particular binary, please remove it. When your datafiles are complete, move them to your home or lab directory (all directories are automounted on kongo just as they are on mbongo). Be aware that any file in /var/tmp not accessed for more than 7 days will be automatically removed. You should consider this area a temporary spot to run your program and access your data to help maximize throughput.
Also, /var/tmp is not backed up to tape. Under most system crashes and reboots, all files in /var/tmp will remain intact (unlike /tmp files). But occasionally a crash may cause some files to be lost.
mbongo and Future Directions
mbongo will still be performing its other duties (for instance, it is the department software license server), and will be taking on other functions such as the department gopher server coming soon, thus freeing kongo to act solely as the departmental Instructional compute server.
We hope to upgrade kongo in the future to a multiprocessor system through CPU module upgrades. We will probably be adding more disk in the future, too. We consider this initial configuration a good starting point considering the available funds.
kongo is meant to supplement the Instructional compute-intensive needs in the department along with the use of the vast resources at SDSC. Several packages which are SPARC binary-only and code which does not easily port to SDSC systems are just a couple reasons why we need some kind of local compute server. Users are still encouraged to evaluate the SDSC supercomputer and multiprocessor systems for heavy compute- and memory-intensive, long-running processes. Block grant applications for accounts on SDSC resources can be obtained from Rick Ord (ricko@cs).
Glenn Little -- CSE Systems Support Group
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