Chapter 6 HPSS Configuration310 September 2002 HPSS Installation GuideRelease 4.5, Revision 2Stripe Transfer Rate The approximate datatransfer rate for the entirestripe.This value is calculated by SSM. Itis the product of the Device I/ORate and Stripe Width fields.Same asDevice I/ORate.Blocks Between TapeMarksThe maximum number ofdata blocks that can bewritten on a tape betweenconsecutive tape marks.This field is applicable totape storage classes only.Any positive 32-bit integer value. Based onselectedMedia Type.Advice: The number of blocks between the physical volume tape marks should bechosen to use the media efficiently while allowing for quick positioning to a tapemark. See Section 2.9.1.5 for more details.Seconds Between TapeMarksThe number of secondsbetween tape mark writesduring a tape writeoperation derived fromBlocks Between TapeMarks and Device I/ORate. This field isapplicable to tape storageclasses only.Any positive 32-bit integer value. Based onselectedMedia Type.Advice: Enter a value into the Blocks Between Tape Marks field, and use SecondsBetween Tape Marks value for feedback on the resulting time interval; or enter avalue into the Seconds Between Tape Marks and let SSM calculate the BlocksBetween Tape Marks value. Changing either field automatically modifies the otherone. As a rule of thumb, it is best to choose “Blocks Between Tape Marks” such that5 to 30 seconds elapse.Minimum Storage SegmentSizeThe smallest allocatableunit of disk space. Thisfield is applicable to diskstorage classes only.Click on the option menu button topop up a list of acceptable sizes.ClusterLength.Advice: Care should be taken in selecting the Storage Segment Size. Consult Section2.9.1.6 for considerations related to this selection.Maximum Storage SegmentSizeWhen this field is largerthan the Storage SegmentSize, the Bitfile Server isallowed to use multiplestorage segment sizes fordisks in this storage class,up to this maximum.Click on the option menu button topop up a list of acceptable sizes.Same asStorageSegment Size.Advice: If a value larger than 10 percent of PV Size is specified, the user will bewarned of non-optimal use of disk space.Table 6-11 Storage Class Configuration Variables (Continued)Display Field Name Description Acceptable Values DefaultValue
