Also in development at this time was a fileserver for AppleBus (later renamed AppleTalk), based on a stripped-down Macintosh with a 68000 CPU and internal Nisha hard disk.īurrell Smith was designing the Turbo Mac with Brian Howard and Bob Bailey, recalls Andy Hertzfeld in his Folklore blog. It was intended to be "a faster Mac in the original Mac box, but the project was scrapped in early 1985." At this time, Macintosh engineers were working on a number of next-generation Macintosh architectures utilizing the new Motorola 68020 CPU, with code names such as Jonathon, Big Mac, Little Big Mac, and Reno. Allen's book, "On Macintosh Programming," the Turbo Mac project began in late 1984. So while our file system is optimized for these small disks, you can have a whole 'nother way of storing it out on a hard disk."Īccording to Daniel K. In an interview with Finder authors Bruce Horn and Steve Capps, published in ST.Mac March 1984, Capps hints at a new file system needed for hard disks, stating, "There's a concept built into the ROM of completely external file systems. So then, what were the Macintosh designers thinking? How could they have overlooked such a necessity as hard disk storage at the time? The answer is that they had something different in mind. (above: The Davong Mac Disk, as shown in Macworld December 1984) The limitations of the Finder and MFS made them even more miserable early reviews of them in InfoWorld and other magazines were less than stellar. The first two hard drives for Macintosh, available in mid-1984, the 10 MB Davong Mac Disk (shown below) and 5/10 MB Tecmar Mac Drive, already suffered from the Mac's slower serial port. Folders in fact were kept as "Finder Objects" in the Desktop file. The Macintosh File System was not a true hierarchical system it only appeared to be in the Finder. Moreover, the Finder had to maintain the catalog in RAM to keep track of folders, which were illusory. The Macintosh catalog, on the other hand, topped out at around 128 files on a 400K disk (note that 128 is not a limit of MFS, but is a limit of the typical number of catalog tracks on a 400K disk- you could format an MFS disk with more catalog tracks to hold a larger catalog if you wanted). The Lisa disk catalog could hold around 1,200 files. File labels were a way of keeping file data separate from the information maintained about the file. But the third version (Lisa OS 3.0) had a fairly sophisticated file system that supported true hierarchical directories using a B-Tree structure, access privileges, concurrent file access from multiple processes, pipes, and file labels. The first two did not support subdirectories and had a single catalog table. The Apple Lisa had three file system versions. Magazine interviews with Macintosh developers from 1984 hint at this: neither MFS, nor the Finder, nor the serial ports used to connect a hard disk were suited to having more than 1 MB or so worth of files. While the Lisa had a 5 MB ProFile hard disk system (a 10 MB drive was available later), it appears that directly-connected mass storage for the Macintosh was never seriously contemplated. When the Macintosh team switched over to Sony's single-sided 3.5" drive in May 1983, they kept the same file system, but the disk capacity was halved to 400KB. I don't have any documentation yet to firmly support this statement, but my impression is that the Macintosh File System was based upon the Lisa file system which in turn was similar to a file system developed by Xerox for its Star workstation. The Macintosh had provision for an external Twiggy, meaning that about 1.5 MB of storage could be online at a time. The Twiggy, a double-sided drive, allowed for 860KB of storage. Up until around mid-1983, the Macintosh used the same 5.25" Twiggy disk drive as used on the Lisa. Comments in the MFS source code show that file system development began in early 1982, and data structures were redesigned in December 1982. Larry Kenyon designed the first file system for Macintosh, known simply as MFS: Macintosh File System. Your support is needed and is appreciated as is primarily dependent upon the support of its users.Now that Apple has recently switched to a new file system for Mac OS X, it's interesting to take a look back at HFS, which recently turned 32 years old, and which served, with many modifications and extensions over the years, as the primary file system for the Macintosh.
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