Sector interleave (was: H89 CP/M hard-secored boot diskette

On Thu, 3 Apr 2003, ben franchuk wrote: It also depends on what kind of processinbg is being done to it during loading. For example, dumping file contents into RAM can be done a lot faster than loading a document into a word-processor. The fastest interleave occurs if the system can handle the next sector immediately after the previous. In that case, the fastest sequence is plain sequential, and a track can be read in a single revolution. But when you add extra processing of the data during reading, (such as a word processor loading a document), you could end up with NOT being ready for the next sector in time, resulting in the read taking as many revolutions of the disk as there are sectors per track. Alternating sectors might reduce that to two revolutions (or skipping 2 sectors, etc.), but that can easily be twice as long as necessary for a task that did NOT need the extraneous processing. Most system software developers DO think that they have optimized it. But they have optimized it for the type of file access that they EXPECT you to be doing (usually whatever THEY do most). BTW, it can be done either by placing the physical sectors in various orders (such as 1,3,5,7,9,2,4,6,8,10) OR can be done by a translation between logical sector and physical sector (physical sectors numbered 1,2,3,4, . . . , but data that doesn't finish in sector 1 continues in sector 3, etc.)