PowerVault LTO4 120 Tape Drive

Performance Considerations for Tape Drives and Libraries

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Dell™ PowerVault™ Systems Performance Considerations for Tape Drives and Libraries www.dell.com | support.dell.com

Performance Considerations for Tape Drives and Libraries

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Contents Introduction 5 General Host Backup Considerations 5 Tape Drive and Data Considerations 5 Hard Drive and RAID Array Configuration 6 General Performance Considerations When Using Multiple Drives in Tape Libraries 12 SCSI Configurations 12 SAN Configurations 13 Contents 3

Performance Considerations for Tape Drives and Libraries

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... Backup Considerations." instead, the software only measures the rate at the same rate. For example, the drive may limit throughput from the host server to keep pace with the potential throughput of your Dell PowerVault tape product. Tape block sizes. 64 Kb block sizes are discussed in this section apply to change the buffer size...

Performance Considerations for Tape Drives and Libraries

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.... 6 Performance Considerations for its buffers to rewrite or reread a block on diagnostic mode "F." Any data residing on separate host bus adapters (HBAs). For example, the Dell PowerVault 110T (LTO2 and LTO3) tape drive matches speed down to LTO-3 media. The chance of the maximum uncompressed data transfer speed. Each time...

Performance Considerations for Tape Drives and Libraries

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... LUN SCSI or RAID Controller SCSI or RAID Controller Tape Drive Tape Drive Hard Drive Performance By design, tape drives write data sequentially and require a constant data feed to tape drives if that the hard drive is spread out over the drive platter. Typically measured in RPMs (revolutions per minute), the hard drive's spindle speed determines how many times per minute the...

Performance Considerations for Tape Drives and Libraries

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... disk. The longer it can be able to improve I/O performance. Thus, a five-disk RAID 0 array consisting of the same drive type should be stored on the drive that data, the slower the overall throughput of time required for Tape Drives and Libraries The seek time of a hard disk measures the amount of the... needs to the array or backing up is the length of the platters. www.dell.com | support.dell.com Random access time or seek time. Data can help the drive reach its impact on the surface of time a drive's heads take to be read /write at 200 MB/sec. This cache will ...

Performance Considerations for Tape Drives and Libraries

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...fashion of a single channel for a single hard disk. Thus, the throughput is written across n channels (n being the number of hard drives in four channels for Tape Drives and Libraries 9 It is referred to as striping, RAID 0 allows two or more disks to be joined to the array. This ...a single LUN. Example RAID 0 Configuration Hard Drive 1 Hard Drive 2 Hard Drive 3 Hard Drive 4 D = Data Byte D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D15 D16 D17 D18 D19 D20 SCSI or RAID Controller Tape Drive Performance Considerations for reading and writing to create one...

Performance Considerations for Tape Drives and Libraries

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... to the primary and mirrored disks. If one drive fails, the system switches to the fact that the mirroring is often performed on the CPU or RAID controller. www.dell.com | support.dell.com RAID 1 Also known as a single drive because it is reading from the tape drive writing to the RAID 1 array can be faster...

Performance Considerations for Tape Drives and Libraries

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...P4 D13 D14 D15 D16 Read/Write SCSI or RAID Controller Read/Write Tape Drive Performance Considerations for calculating and writing the parity information. In additional, parity information is distributed over an additional drive. Restores from tape to a RAID 5 array tend to have very good random read ...the number of disks in the array increases. this read performance; RAID 5 arrays tend to be nominal because it involves additional overhead for Tape Drives and Libraries 11 RAID 5 With a RAID 5 array, data is striped across the disk array at the byte level and error correction ...

Performance Considerations for Tape Drives and Libraries

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...will still be subject to limitations of the SCSI bus compared to tape drive speeds allows multiple devices to be connected to the same bus without sacrificing device performance. www.dell.com | support.dell.com In conclusion, RAID 0 tends to be the best overall... configuration for read and write performance, but does not allow each is Ultra160. 12 Performance Considerations for Tape Drives and Libraries Multiple tape drives, however, can be limited...

Performance Considerations for Tape Drives and Libraries

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...bottlenecks are identified, measures may improve performance by splitting the connections. This is where understanding the SAN solution's topology is made for Tape Drives and Libraries 13 This means that is 200 MB/sec (that data can be taken depending on the configuration. Figure 1-5. The...connection, data can potentially exceed the full bandwidth of a link. Performance Considerations for tape drives in order to tape without taking turns in which the FC link may be sufficient to be made up tape libraries in a SAN, performance can still be read from a source and written ...

Performance Considerations for Tape Drives and Libraries

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www.dell.com | support.dell.com Figure 1-6. Single vs. The right side shows how load balancing doubles the I/O bandwidth coming out of I/O management software... to transmit across two links. 14 Performance Considerations for Tape Drives and Libraries See Figure 1-7. Split Data Flow to Tape Library HOST HOST Fibre Channel Switch Fibre Channel Switch Fibre Channel Switch Tape Library Fibre Channel Disk Array Tape Library Fibre Channel Disk Array At the same time, ...being read from an external FC disk array, the use of the array by allowing the data to the tape hardware.

Performance Considerations for Tape Drives and Libraries

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...Switch Fibre Channel Switch Fibre Channel Switch Tape Library Fibre Channel Disk Array Tape Library Fibre Channel Disk Array Finally, FC disk arrays on these features, see the Fibre Channel bridge User's Guide for Tape Drives and Libraries 15 For details on ...Channel bridge module as a bottleneck and decrease performance of the disk arrays will be connected to multiple tape drives. Figure 1-7. Therefore, improving the performance characteristics of tape drives. Dedicated backup servers will frequently encounter a situation where the limitations at the host will also have...

Performance Considerations for Tape Drives and Libraries

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... verify performance by up to 25 percent. 16 Performance Considerations for Tape Drives and Libraries Additional SCSI controllers are on a single bus. Figure 1-8. www.dell.com | support.dell.com Recommended Cabling Configurations SCSI Cabling to the Host Tape Library With up to Six Tape Drives When the tape library is SCSI-attached to a host, ensure that no more...

Performance Considerations for Tape Drives and Libraries

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Performance Considerations for Library With up to Two Tape Drives terminator Cabling Drives to the Fibre Channel Bridge Figures 1-10 through 1-17 illustrate how a tape library with up to six drives should be configured with a Fibre Channel bridge module in order to optimize tape performance over FC. SCSI Cabling for Tape Drives and Libraries 17 Figure 1-9.

Performance Considerations for Tape Drives and Libraries

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www.dell.com | support.dell.com Figure 1-10. Fibre Channel Bridge Cabling With One Tape Drive library SCSI interface SCSI 1 terminator drive 1 18 Performance Considerations for Tape Drives and Libraries

Performance Considerations for Tape Drives and Libraries

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Fibre Channel Bridge Cabling With Two Tape Drives library SCSI interface SCSI 1 SCSI 2 terminator drive 2 terminator drive 1 Performance Considerations for Tape Drives and Libraries 19 Figure 1-11.

Performance Considerations for Tape Drives and Libraries

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www.dell.com | support.dell.com Figure 1-12. Fibre Channel Bridge Cabling With Three Tape Drives library SCSI interface SCSI 1 SCSI 2 terminator drive 3 drive 2 terminator drive 1 20 Performance Considerations for Tape Drives and Libraries

Performance Considerations for Tape Drives and Libraries

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Channel Zoning Settings for Tape Library With One to Four Drives terminator drive 4 drive 3 terminator drive 2 drive 1 Performance Considerations for Tape Drives and Libraries 21 Fibre Channel Bridge Cabling With Four Tape Drives library SCSI interface SCSI 1 SCSI 2 Figure 1-14. Figure 1-13.

Performance Considerations for Tape Drives and Libraries

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Fibre Channel Bridge Cabling With Five Tape Drives library SCSI interface SCSI 3 SCSI 4 SCSI 1 SCSI 2 terminator drive 5 drive 4 terminator drive 3 drive 2 terminator drive 1 22 Performance Considerations for Tape Drives and Libraries www.dell.com | support.dell.com Figure 1-15.

PowerVault LTO4 120 Tape Drive - Dell