Chapter 6 HPSS Configuration312 September 2002 HPSS Installation GuideRelease 4.5, Revision 26.7.1.2 Storage Subsystem Specific ThresholdsIf different Warning and Critical Thresholds are desired for a storage class in different storagesubsystems, it is possible to override the default values. By default, the Warning and CriticalThresholds specified on the Storage Class Configuration window are applied to that storage classAverage Latency The average time (inseconds) that elapses whena data transfer request isscheduled and the time thedata transfer begins. Thisfield is only applicable totape storage classes.Any positive 32-bit integer value. Based onselectedMedia Type.Advice: For additional information relating to the selection of storage systemcharacteristics fields, refer to Section 2.9.3.5.Maximum VVs to Write The number of tape virtualvolumes in the storageclass that a Tape StorageServer will use forconcurrent writes. Thisfield is only applicable totape storage classes.Any positive 32-bit integer value. 10.Advice: Small values in this field restrict files being written in the storage class to asmall number of tapes, reducing the number of tape mounts. The number of tapedrives used to write files in the storage class will be limited to approximately thevalue of this field times the stripe width. Read operations are not limited by thisvalue.Average Number of StorageSegmentsIf the Maximum StorageSegment Size field isgreater than the StorageSegment Size field, theBitfile Server attempts toselect a storage segmentsize for a bitfile such thatthe bitfile can be stored inthis number of storagesegments. This field isonly applicable to diskstorage classes.Any positive 32-bit integer valuelimited by the maximum number ofVVs created for the storage class.4.Advice: The number of Storage Segments of a particular file that can be storedsimultaneously on tape is unlimited; however, no file can have more than 10,000 diskstorage segments at any one time. Also, increasing the number of storage segmentswill increase the amount of metadata activity required to process file reads andwrites. So it is a good idea to keep this number low.Table 6-11 Storage Class Configuration Variables (Continued)Display Field Name Description Acceptable Values DefaultValue
