Development and Implementation of a File System for Gannet Virtual ...
Development and Implementation of a File System for Gannet Virtual ...
Development and Implementation of a File System for Gannet Virtual ...
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3.2.1.1 <strong>File</strong> <strong>System</strong> Layout<br />
<strong>Gannet</strong>FS file system is a logical entity with inodes <strong>and</strong> data blocks. From higher<br />
level point <strong>of</strong> view, <strong>Gannet</strong>FS consist <strong>of</strong> an array <strong>of</strong> data blocks which is managed<br />
<strong>and</strong> marshaled by two stacks data structure.<br />
Initial Design <strong>of</strong> Data Object Layout<br />
The initial design to organize the data object on <strong>Gannet</strong>FS file system is by using two<br />
types <strong>of</strong> arrays to accommodate the metadata file <strong>and</strong> data file, respectively. This<br />
array contains number <strong>of</strong> fixed allocated memory called block. Each type <strong>of</strong> array<br />
has a stack to manage the allocation <strong>of</strong> block as illustrated on diagram below.<br />
Stack<br />
<br />
Stack<br />
<br />
Inodes Blocks<br />
Figure 3.1 Illustration initial design <strong>of</strong> data object<br />
Stack has function to manage the allocation <strong>for</strong> blocks by storing a set <strong>of</strong> free blocks.<br />
As the system needs a block to store a file or metadata, the stack returns an address<br />
<strong>of</strong> free block <strong>and</strong> pop the address out <strong>of</strong> the stack. If the system has freed the<br />
allocation <strong>of</strong> a block, the address <strong>of</strong> unused block is inserted to the stack. Hence, by<br />
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