code: mafs

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updated document

--- a/docs/mafs.ms

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 Extents

 .ft R

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-Free blocks and memory are managed using Extents, an abstraction used to manage a continuous list of items.

+This is a more elaborate version of the storage allocator described in Section 8.7 of the K & R C Programming language book. It differs from the allocator described there by being a "Best first fit" instead of a "first fit". Also, instead of a circular linked list of free blocks, we maintain the free blocks in two doubly linked lists, one by start address and another by size and start address. We also maintain a list of recently used blocks to reduce the travel by linear scans.

 .sp

+Extents is an abstraction used to manage contiguous units. It is responsibility of the caller to manage the size and scaling of each unit.

+.sp

+Free blocks, memory and long names strings are managed using Extents.

+.sp

 An Extent represents a continuous list of items. An Extents is a list of such Extent's.

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@@ -1644,3 +1648,5 @@

 [1] Sean Quinlan, "A Cached WORM File System," Software--Practice and Experience, Vol 21., No 12., December 1991, pp. 1289-1299

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 [2] Ken Thompson, Geoff Collyer, "The 64-bit Standalone Plan 9 File Server"

+.br

+[2] Brian Kernighan, Dennis Ritchie, "The C Programming Language"