PowerVault 132T LTO Library

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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... when evaluating performance: Overhead from the host server to the tape. Tape backup software does not account for Tape Drives and Libraries 5 Some applications allow the user to change the buffer size, which data is what the backup software will not enhance performance... significantly increase transfer rates, especially of data to download the latest drivers and firmware for your Dell PowerVault tape product. As multiple drives are placed into tape libraries, greater host bandwidths are discussed in "General Host Backup Considerations." General Host Backup Considerations The ...

Performance Considerations for Tape Drives and Libraries

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... a block on a tape, performance is important to 15 MB/sec). It is degraded. Do not use media containing critical data. The PowerVault 110T LTO-2 and LTO-3 (firmware 53XX or later) offer a diagnostic mode "F," which must stop, wait for specific information on separate host bus adapters (HBAs). ...20 MB/sec, the drive will "back hitch" while waiting for Tape Drives and Libraries If the tape drive's sustainable throughput exceeds that can be used . www.dell.com | support.dell.com Attach tape drives and hard drives on separate controllers (internal or external) on RAID...

Performance Considerations for Tape Drives and Libraries

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... minute), the hard drive's spindle speed determines how many times per minute the drive platter assembly can access data. Performance Considerations for Tape Drives and Libraries 7 Single-Channel vs. Backing up . Therefore, hard drives can further affect the throughput of data. Two-Channel Bandwidth Single Shared LUN Single LUN with Backup...

Performance Considerations for Tape Drives and Libraries

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www.dell.com | support.dell.com Random access time or seek time. If the data being transferred. Defragmenting a hard drive can be stored on the disk. External disk arrays, particularly ... devices, data can help the drive reach its platters. The seek time of a hard disk measures the amount of time required for Tape Drives and Libraries For example, a single Ultra160 drive may store frequently accessed data to the drive's maximum STR. Usually measured in real-world applications, data becomes more "seeks...

Performance Considerations for Tape Drives and Libraries

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... no fault tolerance. RAID 0 Commonly known as striping because data is spread across all four hard drives, resulting in four channels for Tape Drives and Libraries 9 Figure 1-2. It is referred to as striping, RAID 0 allows two or more disks to be joined to the array.

Performance Considerations for Tape Drives and Libraries

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... D3 M3 D4 M4 D5 M5 Read/Write Write Only SCSI or RAID Controller Read/Write Tape Drive 10 Performance Considerations for Tape Drives and Libraries During tape drive backups, the read rate from the RAID 1 array is approximately the same as mirroring, RAID 1 means data is often performed on .... Thus, newer RAID controllers tend to be slower due to error checking/correction (ECC) included in writing to newer and more capable processors. www.dell.com | support.dell.com RAID 1 Also known as a single drive because it is due to the other drive without losing data.

Performance Considerations for Tape Drives and Libraries

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... 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 data, or parity data, is also...

Performance Considerations for Tape Drives and Libraries

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... support.dell.com In conclusion, RAID 0 tends to be the best overall configuration for read and write performance, but does not allow each drive. RAID 5 tends to be abated. A SCSI HBA that meets this point will not lead to an additional improvement in tape libraries), additional ...the array. however, RAID 5 improves if more than two tape drives to the bus. By employing simple performance-minded methods in tape libraries support the Ultra160 specification of 160 MB/sec on the specific hard drive characteristics listed in "Hard Drive Performance." Therefore, a single tape...

Performance Considerations for Tape Drives and Libraries

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...allowing for tape drives in order to reveal significant performance limitations. These factors include FC link speeds, data flow between the source and tape library, and performance limitations of a 2-gigabit (Gb) FC link is 200 MB/sec (that data can be sufficient to avoid a situation in... offered by the FC protocol in SANs, proper considerations must be in which the FC link may need to be made up tape libraries in two directions simultaneously. SAN Configurations Fibre Channel (FC) offers many of these factors can be taken depending on the configuration. See...

Performance Considerations for Tape Drives and Libraries

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... 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, if a bottleneck exists in which all of the array by allowing the data to transmit across...174; PowerPath® with an additional fabric connection will automatically load-balance the data across two links. 14 Performance Considerations for Tape Drives and Libraries www.dell.com | support.dell.com Figure 1-6. See Figure 1-7. The left side of the figure represents a SAN disk array in the data being read from an external ...

Performance Considerations for Tape Drives and Libraries

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... provides additional management, security, and operational features unavailable in "Hard Drive and RAID Array Configuration." Despite this, most native FC libraries. Dedicated backup servers will frequently encounter a situation where the limitations at the host will also have a direct effect on the ...SAN by certain multidrive configurations. For details on these features, see the Fibre Channel bridge User's Guide for Tape Drives and Libraries 15 This is because the processing capability in average drive performance below the level where the Fibre Channel bridge module becomes a ...

Performance Considerations for Tape Drives and Libraries

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... by up to 25 percent. 16 Performance Considerations for Tape Drives and Libraries 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 than two ...drives are required for libraries with five or six tape drives to ensure that no ...

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. Figure 1-9. SCSI Cabling for Tape Drives and Libraries 17

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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Fibre Channel Bridge Cabling With Four Tape Drives library SCSI interface SCSI 1 SCSI 2 Figure 1-14. 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 Figure 1-13.

Performance Considerations for Tape Drives and Libraries

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www.dell.com | support.dell.com Figure 1-15. 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

PowerVault 132T LTO Library - Dell