title: Block-Based Distributed File Systems

authors: McGregor, Anthony James

subjects: Distributed file systems

abstract: Distributed file systems have become popular because they allow information to be shared be between computers in a natural way. A distributed file system often forms a central building block in a distributed system.

Currently most distributed file systems are built using a communications interface that transfers messages about files between machines. This thesis proposes a different, lower level, communications interface. This `block-based' interface exchanges information about the blocks that make up the file but not about the files themselves. No other distributed file system is built this way.

By demonstrating that a distributed file system can be implemented in a block-based manner, this thesis opens the way for many advances in distributed file systems. These include a reduction of the processing required at the server, uniformity in managing file blocks and fine-grained placement and replication of data. The simple communications model also lends itself to efficient implementation both at the server and in the communications protocols that support the interface. These advantages come at the cost of a more complex client implementation and the need for a lower level consistency mechanism. 
A block-based distributed file system (BB-NFS) has been implemented. BB-NFS provides the Unix file system interface and demonstrates the feasibility and implementability of the block-based approach. Experience with the implementation lead to the development of a lock cache mechanism which gives a large improvement in the performance of the prototype. Although it has not been directly measured it is plausible that the prototype will perform better than the file based approach.

The block-based approach has much to offer future distributed file system developers. This thesis introduces the approach and its advantages, demonstrates its feasibility and shows that it can be implemented in a way that performs well.

text: Block-Based Distributed File Systems Distributed file systems have become popular because they allow information to be shared be between computers in a natural way. A distributed file system often forms a central building block in a distributed system.

Currently most distributed file systems are built using a communications interface that transfers messages about files between machines. This thesis proposes a different, lower level, communications interface. This `block-based' interface exchanges information about the blocks that make up the file but not about the files themselves. No other distributed file system is built this way.

By demonstrating that a distributed file system can be implemented in a block-based manner, this thesis opens the way for many advances in distributed file systems. These include a reduction of the processing required at the server, uniformity in managing file blocks and fine-grained placement and replication of data. The simple communications model also lends itself to efficient implementation both at the server and in the communications protocols that support the interface. These advantages come at the cost of a more complex client implementation and the need for a lower level consistency mechanism. 
A block-based distributed file system (BB-NFS) has been implemented. BB-NFS provides the Unix file system interface and demonstrates the feasibility and implementability of the block-based approach. Experience with the implementation lead to the development of a lock cache mechanism which gives a large improvement in the performance of the prototype. Although it has not been directly measured it is plausible that the prototype will perform better than the file based approach.

The block-based approach has much to offer future distributed file system developers. This thesis introduces the approach and its advantages, demonstrates its feasibility and shows that it can be implemented in a way that performs well.

year: 1997

title: Unlocking curious minds evaluation report: Developing a STEM mobile makerspace and maker educator learning resources

authors: Khoo, Elaine G.L.

abstract: This report details our research project funded under the Unlocking Curious Minds initiative 2020. It was conducted in parallel with the makerspace programme: Building a city of the Future 2040. This report describes the project aims, rationale, the City of the Future themed intervention, and findings of the developmental initiative

text: Unlocking curious minds evaluation report: Developing a STEM mobile makerspace and maker educator learning resources This report details our research project funded under the Unlocking Curious Minds initiative 2020. It was conducted in parallel with the makerspace programme: Building a city of the Future 2040. This report describes the project aims, rationale, the City of the Future themed intervention, and findings of the developmental initiative

year: 2021

title: Kōauau auē, e auau tō au e! The Kōauau in Te Ao Māori.

authors: Komene, Jo'el

subjects: Kōauau

abstract: In recent years there has been a revival of interest in traditional Māori musical instruments, including the kōauau. This thesis studies kōauau informed by a Māori framework, giving weight to traditional Māori knowledge and practices, emphasizing the spiritual dimensions of the instrument in its origins and its functions. The thesis defines the kōauau and how it is distinct from other taonga pūoro in its physical characteristics. It then presents the traditions associated with the kōauau which link its origins to the atua and their natural world, especially Raukatauri, together with other traditions from many rohe throughout Aotearoa.  The thesis describes the traditional tools and methods of construction, the role of atua in the construction process, materials used for kōauau, how they were embellished, and their use as adornments. The techniques for playing kōauau are analyzed, and there is a discussion of the occasions on which kōauau were played, and the purposes of performing on kōauau. The thesis also presents the texts of several traditional waiata kōauau. A number of traditional kōauau in storage at the Auckland Museum were able to be examined to confirm and extend documentary evidence about materials, construction methods, and embellishment. The discussion also comments on the quot;voicesquot; for those kōauau in the museum collection that could be sounded. The decline in kōauau performance during the twentieth century is outlined, and there is a summary of successful efforts in the later twentieth century to revive taonga pūoro, including kōauau. The thesis brings together in concise form much scattered information so that current and future performers with kōauau are able to give full consideration to its place in te ao Māori.

text: Kōauau auē, e auau tō au e! The Kōauau in Te Ao Māori. In recent years there has been a revival of interest in traditional Māori musical instruments, including the kōauau. This thesis studies kōauau informed by a Māori framework, giving weight to traditional Māori knowledge and practices, emphasizing the spiritual dimensions of the instrument in its origins and its functions. The thesis defines the kōauau and how it is distinct from other taonga pūoro in its physical characteristics. It then presents the traditions associated with the kōauau which link its origins to the atua and their natural world, especially Raukatauri, together with other traditions from many rohe throughout Aotearoa.  The thesis describes the traditional tools and methods of construction, the role of atua in the construction process, materials used for kōauau, how they were embellished, and their use as adornments. The techniques for playing kōauau are analyzed, and there is a discussion of the occasions on which kōauau were played, and the purposes of performing on kōauau. The thesis also presents the texts of several traditional waiata kōauau. A number of traditional kōauau in storage at the Auckland Museum were able to be examined to confirm and extend documentary evidence about materials, construction methods, and embellishment. The discussion also comments on the quot;voicesquot; for those kōauau in the museum collection that could be sounded. The decline in kōauau performance during the twentieth century is outlined, and there is a summary of successful efforts in the later twentieth century to revive taonga pūoro, including kōauau. The thesis brings together in concise form much scattered information so that current and future performers with kōauau are able to give full consideration to its place in te ao Māori.

year: 2009