Tomohiro Yoshihara

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A new concurrency control protocol for parallel Btree structures, MARK-OPT, is proposed. MARK-OPT marks the lowest structure-modification-operation (SMO) occurrence point during optimistic latch coupling operations, to reduce the cost of SMO compared to the conventional protocols such as ARIES/IM and INC-OPT. The marking reduces the frequency of restarts(More)
The number of stored objects that should be targets of high throughput retrieval, such as multimedia stream objects, is increasing recently. To implement a high throughput storage system, striping technique using multiple disk drives are commonly used. However, the ordinary disk striping methods implemented in RAID 0, 3-5 have problems of the flexibility,(More)
Advanced data engineering applications require a large-scale storage system that is both scalable and dependable. In such a system, an atomic commit protocol becomes imperative to ensure the consistency and atomicity of transactions. In this paper we present a new commit protocol, BA-1.5PC, which is well tailored to such distributed storage environments as(More)
RAID5/6 is widely adopted in enterprise storage systems, despite having a write-penalty problem and consuming the cache memory bandwidth. One of the existing ways for reducing data transfer overhead using XDWRITE/XPWRITE determined in SCSI specification. However, this method still consumes bandwidth because of duplicating the XOR data into cache memories(More)
While shared-nothing parallel infrastructures provide fast processing of explosively growing digital content, managing data efficiently across multiple nodes is important. The value-range partitioning method with parallel B-tree structures in a shared-nothing environment is an efficient approach for handling large amounts of data. To handle large amounts of(More)
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