This thesis investigates the efficiency of extent-based allocatordesign to satisfy file allocation requests in a CDN proxy cache. Theallocator is based on the method inspired by the memory allocators,where free space is managed in chunks of varying size, or extents. Thedesign is tested in a simulation, where a trace of allocation anddeallocation events from a content server was submitted to theallocator. Content serves of this type experience high demands onthroughput, so their file system must store files in the mostefficient way possible. The bottleneck for content retrieval oftenlies on data transfer rates of the hard disks used in the server. Tofacilitate fastest possible transfer of a file, it must be readsequentially, in one operation. At the same time, given the largequantity of file, which are present on such servers, space wastage dueto incomplete utilisation of large allocation units is notdesirable. Our allocator design tries to achieve both, to a certainextent, mutually exclusive goals. The design was implemented and theresults we obtained in the course of simulation, show that we managedto achieve these goals, creating an allocator that displaysproperties, favourable for contiguous file placement, while keepingspace wastage at its minimum. Additionally, the allocator ismemory-efficient and has small bookkeeping and computationaloverhead. The use of our allocator in a CDN proxy file system willallow to keep the data transfer throughput at maximum speed, whileutilising the storage space in an efficient manner. The reader of thisthesis will learn about the allocator semantics and have a detailedintroduction into a specific allocation algorithm, QuickFit. Thisstudy outlines several venues of improvement and opens for a furtherempirical study of complete system, based on the allocator presentedin this thesis.