Adapting to predicted changes in host transmission rates
AssigneeInternational Business Machines Corporation
InventorTakashi Katagiri
Life of this patent
Estimating the term…
Abstract
In one embodiment, a method is provided for adapting a host transfer rate between a host and a tape drive to a medium transfer rate between the tape drive and a tape. A data compression rate of untransferred data in a buffer of a tape drive is measured. A change in a future host transfer rate is predicated based on the measured compression rate. A host transfer rate between a host and the tape drive is adapted to a medium transfer rate between the tape drive and a tape, based on the predicted change.
Claims15
A method for adapting a host transfer rate between a host and a tape drive to a medium transfer rate between the tape drive and a tape, the method comprising:
- measuring a data compression rate X of data recently transferred to a host;
- measuring a data compression rate Y of untransferred data in a buffer of a tape drive;
- measuring a historical transfer rate, wherein the historical transfer rate is an average data transfer rate over a period of time;
- estimating a future host transfer rate D based on the data compression rate Y and the data compression rate X;
- and
- adapting a host transfer rate between the host and the tape drive to a medium transfer rate between the tape drive and a tape, based on the future host transfer rate D.
A tape drive for adapting a host transfer rate of a host to a medium transfer rate of a tape, the tape drive being configured to:
- measure a data compression rate X of data recently transferred to a host;
- measure a data compression rate Y of untransferred data in a buffer of the tape drive;
- measure a historical transfer rate, wherein the historical transfer rate is an average data transfer rate over a period of time;
- estimate a future host transfer rate D based on the data compression rate Y and the data compression rate X;
- and
- adapt a host transfer rate between the host and the tape drive to a medium transfer rate between the tape drive and a tape, based on the future host transfer rate D.
An apparatus, comprising:
- a tape cartridge configured to write compression rate data to tape to enable adaption of a host transfer rate between a host and a tape drive, to a medium transfer rate between the tape drive and the tape,
- wherein the tape cartridge is configured to enable a tape drive, when the tape cartridge is mounted in the tape drive, to write to the tape, as metadata, results of measuring a data compression rate X of data recently transferred to a host, measuring a data compression rate Y of untransferred data in a buffer of the tape drive, measuring a historical transfer rate, wherein the historical transfer rate is an average data transfer rate over a period of time, and to read compression rate data from the tape, such that the tape drive can estimate a future host transfer rate D based on the data compression rate Y and the data compression rate X and adapt the host transfer rate to the medium transfer rate based on the future host transfer rate D.
Dependencies are inferred from the claim text.