The HP LTO Ultrium media compatible designed and manufactured to optimize both the media and drive technology. HP an experiment between the different brands of LTO Ultrium 3 data cartridge backup. The tests prove that users of HP LTO3 Ultrium data cartridges twice the data capacity per backup and was able to significantly improved reliability. HP branded LTO3 Ultrium data cartridges provided for up to three times as many continuously successful backup and restore cycles. The priceHP LTO-3 Ultrium cartridge is less than the other competing brands. Tests under extreme climatic conditions have the reliability of HP LTO Ultrium media, where data has been fully provided by the bands that have survived in the world under extreme conditions again demonstrated.
The test took four engineers LTO3 Ultrium RW cartridges. The two bands were from HP and two others from a leading brand and tested them in four HP StorageWorks Ultrium 960 drives. Test, found in a controlledEnvironment of 74 º C and a relative humidity of 15%.
In the first stage of the procedure, the cartridges through continuous full 100 volumes, 400-GB native capacity, backup and restore were set cycles. This means that the total volume was 200 full-time operations. The bit error rate BER measured every 2 GB throughout the process.
Data error rates to achieve the most informative measure of performance. The data rate also applies to, is made as the band, the signalCharacteristics of the band, the quality of the coating and the roughness of the surface. If the error is high, the drive to work hard to verify that the data is saved or restored properly.
High error rate when the signal is loud and distorted. In the worst case error rate levels ultimately reach a point where can not be corrected with the drive, errors, and data can cope quite lost.
HP has developed proprietary software for the HPDrives, the software acts as a powerful bond microscope and allows the user to analyze the performance of the backup cycles, and again in much more detail than would otherwise be possible using off the shelf backup applications. To ensure that the results of the investigation were overly influenced by the performance of individual drives were the cartridges HP LTO3 Ultrium drives in leading with the other brand tape cartridges for the second stage of the exchangedTests.
In the second stage of testing, the backup tape cartridges complete in 100 volumes of continuous, 400-GB native capacity were tested. The backup, restore cycles and the bit error rate was again measured every 2 GB throughout the process. This brought the total number of backup and restore cycles throughout the test at 400 (200 full-volume backup cycles and 200 full-volume restore cycles). The average error rates were then calculated for each full volume and noDifferences in performance during the tests could then be easily determined by observing a change in error rate.
The results for each of the two HP LTO3 Ultrium cartridges, in each of the drives that were tested in which they were consistently low and stable error rates across the 200 permanent backup and restore 200 continuous cycles. The amount of data was backed up to each cycle also measured to ensure that the backup cartridge was always to provide the full maximum400 GB of data. According to the letter were 80,000 GB data cartridges, the HP still offer optimum performance and maximum capacity without risk of data loss
The results for each of the two other leading brand cartridges, in each of the drives were tested in which they were as consistent, but showed a very different picture. After just 30 full backup and restore 30 cycles, less than one third of the way through the first stage of testing began to affect performance. Afternot more than 60 permanent backup and restore 60 cycles were the error rate so high on both cartridges, that it was no longer possible to complete a full 400-GB backup operation.
Two different types of errors occurred during the tests. These failures were directly to the poor error rate performance. Both types of failure meant that it was not possible to back out of a maximum of 400 GB of data. The first type of error has occurred, as a result reached by the end of the tape beforeCompleted the full capacity of 400 GB backup operation.
Numerous repeated attempts to write to some of the original data were necessary, with more volume with the other leading brand cartridges led as was necessary when using the HP-branded backup media. The second type of disturbance was also stand for the poor error rate performance of the other brand cartridges in context. However, this type of defect in which it was not possible to verify the accuracy of the data written toeven after repeated attempts, so the drive will not and do not cancel the backup operation completely. Both types of failures meant a cleaning cartridge needed to could be used before the test procedure will be continued.
The available capacity with sometimes only 50% of the total capacity will be worse before they are used at the end of the tape. Other leading brand cartridges did not complete the full 100 backup and restore 100 cycles in one of the drives in whichthey were tested.
The high error rate can lead to:
- Reduced capacity cartridge, so you buy more cartridges to back up
- Same amount of data.
- Error backup and restore operations because there are too many errors to correct. You will lose your data.
- More frequent use of a cleaning cartridge.
- Lower speeds (ie less power), because the drive to try again, rewrite or re-read the same payloaduntil they successfully checked in a position that is written or restored data is 100% accurate.
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