In this paper, we propose an iSCSI-APT (iSCSI with Automatic Parallelism Tuning) that maximizes iSCSI throughput in long-fat networks. In recent years, as a protocol for building SANs (Storage Area Networks), iSCSI has been attracting attention for its low cost and high compatibility with existing networking infrastructure. However, it has been known that iSCSI throughput degrades in a long-fat network. iSCSI supports a feature called multiple connections, which allows data delivery over multiple TCP connections in a single session. However, for effective utilization of the multiple connections feature, the number of multiple connections must be appropriately configured according to the network status. In this paper, we propose the iSCSI-APT that automatically adjusts the number of multiple connections according to the network status. Through experiments using our iSCSI-APT implementation, we demonstrate that iSCSI-APT operates quite effectively regardless of the network delay.

In this paper, we propose BDL-APT (Block Device Layer with Automatic Parallelism Tuning) that maximizes the throughput of IP-SAN protocols in long-fat networks. BDL-APT parallelizes data transfer using multiple IP-SAN sessions at a block device layer, and adjusts the number of active IP-SAN sessions automatically according to network status. A block device layer is a layer that receives read/write requests from an application or a file system, and relays those requests to a storage device. BDL-APT automatically optimizes the number of IP-SAN sessions based on the measured network status using our parallelism tuning mechanism based on a numerical computation algorithm, Golden Section Search method. We perform preliminarily investigation on the effectiveness of BDL-APT in realistic network environments using our BDL-APT implementation. Consequently, we demonstrate that our BDL-APT operates effectively in long-fat networks.

Polyethylene non-woven fabric white reflective sheet treatments were applied to 'Saijo' persimmon to improve the coloration of fruits. Persimmon trees with modified leader type training were used in this study. The color chart (CC) value of curtain treatment was significantly increased compared with the control, and no significant difference was observed between curtain and mulch treatments. The sugar contents (°Brix) of fruit among the curtain treatment, mulch treatment, and control were not significantly different. No damage of fruits or twigs was observed in the curtain treatment, and no negative effect was observed in the shelf life of harvested fruits. White reflective sheet use with on-ground mulching has the disadvantage of the sheet becoming dirty during cultivation. On the other hand, curtain treatment using a white reflective sheet can be expected to prolong the useful life of the sheet as well as promote cost reduction. In this study, curtain treatment with white reflective sheet treatments improved the fruit skin color of persimmon.

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