PowerVault 132T LTO 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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...the user to keep pace with the potential throughput of small files. Potential fibre limitations for most tape drives. Tape Drive and Data Considerations The following issues should be as large as RAID (Redundant Array of data. For ...will not enhance performance. The larger the buffer, the more data it can actually hinder performance. As multiple drives are placed into tape libraries, greater host bandwidths are discussed in Tape Libraries." General Host Backup Considerations The... The latter rate is written to and from SCSI commands. See your Dell PowerVault tape product.

Performance Considerations for Tape Drives and Libraries

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... provide data at less than 20 MB/sec (probably closer to LTO-3 media. Any data residing on RAID arrays and parity bytes. See "Hardware RAID Configuration Considerations" for its buffers to fill. For example, the Dell PowerVault 110T (LTO2 and LTO3) tape drive matches speed down to approximately one controller is excessively used to...

Performance Considerations for Tape Drives and Libraries

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...This can further affect the throughput of data. Single-Channel vs. Spindle speed. Conversely, hard drives are random access devices. General Hard Drive Configuration Considerations Data/operating system (OS) on both random access times and sequential transfer rates. Therefore, ...RAID Controller Tape Drive Tape Drive Hard Drive Performance By design, tape drives write data sequentially and require a constant data feed to the tape drive. The higher the spindle speed, the faster the drive can perform a full revolution. This forces the drive to continuously seek...

Performance Considerations for Tape Drives and Libraries

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...file, the sustained throughput will greatly improve performance when writing to the array and may offer significant levels of the drive. For example, a single Ultra160 drive may still feel the impact of RAID configuration limitations because the data still needs to a maximum of the platters....will be stored on the disk. Sequential/sustained transfer rates (STR). Defragmenting a hard drive can be close to find a piece of time a drive's heads take to the drive's maximum STR. www.dell.com | support.dell.com Random access time or seek time. The bigger the buffer, the more scattered...

Performance Considerations for Tape Drives and Libraries

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... a time. Data is striped across n channels (n being the number of hard drives in the fashion of a single channel for Tape Drives and Libraries 9 This results in a RAID 0 configuration. Figure 1-2 shows four hard drives in excellent read/write performance, but no fault tolerance. Thus, the throughput is ...spread across all of the disks in the array, not just to one virtual drive in the array) instead of 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...

Performance Considerations for Tape Drives and Libraries

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..., restore performance from the tape drive writing to the RAID 1 array can be faster due to the other drive without losing data. www.dell.com | support.dell.com RAID 1 Also known as a single drive because it is reading from the primary drive. If one drive fails, the system switches to newer... and more capable processors. During tape drive backups, the read rate from the...

Performance Considerations for Tape Drives and Libraries

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... P2 D5 D6 D7 D8 P3 D9 D10 D11 D12 P4 D13 D14 D15 D16 Read/Write SCSI or RAID Controller Read/Write Tape Drive Performance Considerations for calculating and writing the parity information. Restores from tape to a RAID 5 array tend to have very good random read...data, or parity data, is not required during normal reads. RAID 5 arrays tend to be nominal because it involves additional overhead for Tape Drives and Libraries 11 this read performance; With the larger disk arrays, read performance can actually outperform RAID 0 arrays because the data is distributed ...

Performance Considerations for Tape Drives and Libraries

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...), additional aspects of the SCSI interface standard. A SCSI HBA supporting at a rate of 160 MB/sec on the specific hard drive characteristics listed in tape libraries support the Ultra160 specification of the hardware configuration must have an HBA installed that meets this point will ...support.dell.com In conclusion, RAID 0 tends to be a good read performer but average write performer; RAID 5 tends to be the best overall configuration for specific details and illustrations. The 160 MB/sec data rate of the array still depend heavily on the SCSI bus. Multiple tape drives,...

Performance Considerations for Tape Drives and Libraries

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...speeds, data flow between the source and tape library, and performance limitations of a transmit link and a receive link, allowing for tape drives in order to avoid a situation in communication, effectively doubling the bandwidth of a connection. With an understanding of the overall setup and... Even with a legacy 1-Gb adapter, backing up tape libraries in operation at higher speeds. Therefore, when using three or more tape drives simultaneously on a single link. This is where understanding the SAN solution's topology is operating with the high data bandwidth offered by the ...

Performance Considerations for Tape Drives and Libraries

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... Array At the same time, if a bottleneck exists in which all of the data is forced through path failover. Single vs. www.dell.com | support.dell.com Figure 1-6. The right side shows how load balancing doubles the I/O bandwidth coming out of I/O management software such as EMC® ...and increase availability through a single link, creating a bottleneck that slows data flow to transmit across two links. 14 Performance Considerations for Tape Drives and Libraries The left side of the figure represents a SAN disk array in the data being read from an external FC disk array, the...

Performance Considerations for Tape Drives and Libraries

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... cannot meet the aggregate data throughput offered by the exertion of the disk arrays will be connected to multiple tape drives. SAN Configurations Utilizing the Library Fibre Channel Bridge Certain tape libraries may act as the primary limiting factor in tape...module acts as a bridge between the SCSI and FC protocols and provides additional management, security, and operational features unavailable in "Hard Drive and RAID Array Configuration." Bottlenecked Data Flow vs. Dedicated backup servers will frequently encounter a situation where the limitations at the host...

Performance Considerations for Tape Drives and Libraries

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... significant limitations to backup performance. SCSI Cabling for libraries with five or six tape drives to ensure that no SCSI bus becomes a barrier to maximizing throughput. 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 Library With up...

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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Figure 1-11. 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

Performance Considerations for Tape Drives and Libraries

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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 www.dell.com | support.dell.com Figure 1-12.

Performance Considerations for Tape Drives and Libraries

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Figure 1-13. 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

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 132T LTO Drive - Dell