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A system of asynchronously writing tape drive

IP.com Disclosure Number: IPCOM000237742D
Publication Date: 2014-Jul-09
Document File: 4 page(s) / 86K

Publishing Venue

The IP.com Prior Art Database

Abstract

The disclosure discloses a new asynchronous tape drive system, which allows multipul clients to send data simultaneously. Different I/O streams from multiple clients can be serialized by this new tape drive system and written to tape asynchronously. Thus the reading/writing rate of tape drive can be fully exploited and the efficiency can be highly improved.

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A system of asynchronously writing tape drive

Tape is widely used in the storage system as the back end media. The reading/writing rate of tape has been increased steadily and dramatically due to theimprovement of hardware technology, whereas the data transfer speed from the clients can be much slower. Since the tape drive is reserved exclusively by a specific hostduring the whole data transfer time period, it leads a problem that the reading/writing rate of tape usually cannot be fully occupied and the efficiency is impaired.

Therefore, based on the current host data transfer speed, it is becoming a hot topic that how one can exploit the high drive data rate and increase the efficiency.

A new system of asynchronously writing tape drive is proposed in this invention. Multiple hosts can write data to the tape drive simultaneously. Instead of exclusively reserving the tape and waiting until all data written to the tape, hosts send data to the tape drive and return directly without wait. Different I/O streams from multiple clients can be serialized by this new tape drive system and written to tape asynchronously. After finish writing, hosts are signalled about the result and the exactly written position as well.

To implement this, each tape drive has its own cache. Host's data is sent to the cache, and different I/O streams from cache are serialized by the asynchronous tape drive system and written to tape accordingly.

Below is the storage system architecture graph:

Storage Environment over SAN

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And the detailed steps are described as follows:

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Therefore in a SAN environment, multiple hosts may connect and write to the same tape drive simultaneously. When hosts have data to be written, detail steps are described as follows:

1. Stora...