> f.. Data were only transferred for a short while from the BRAHMS DAQ to RCF. (Monday evening). HPSS returned errors. > g.. Since Phobos did not take part in this MDC Bruce will like to repeat this likely by end of February. > h.. Star achieved DAQ -> HPSS sustained rates of 18Mb/sec over the 2 days. > ------------------------------ The failure in the DAQ to HPSS transfers was traced to an error in my script. I was misinterpreting the HPSS error and was not creating the right directory before trying to "pput" a file into it. After the error was corrected, the data started moving again, at peak transfers rates of 12-16 Mbytes/sec. This is a bit low (the disk spool on opus should sustain up to 20 Mbytes/sec), but consistent with the STAR numbers (they use MTU=9000 "jumbo" frames, we use MTU=1500, so their data ought to move faster). While running the sending scripts I see a lot of HPSS "hickups", for example, sometimes HPSS logins "hang" and some HPSS commands sometimes take a long time to complete. Also, Tom Throwe's scripts that report free HPSS disk cache space no longer work, and I now can easily (and happily did) use up all the cache space. Tom is working on fixing this problem. -- Konstantin Olchanski Physics Department, Brookhaven National Laboratory, Long Island, New York olchansk@bnl.gov
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