moore@NCSC.ARPA.UUCP (03/11/87)
Does TWISTER.PRG, published in this quarter's STart, work? [Background: the program formats floppies such that each track has its sector numbers offset by two from the previous track, so that double reads of a single track caused by seek and settle times are eliminated]. It sure sounds like it should work, but I don't notice any difference at all! I "twisted" one disk and formatted (extended) another, then copied the same files (about 220K) to each; then I copied each to an extended formatted disk. The results, plus or minus any irregularities caused by my timing method (a Casio stopwatch), are identical. The extended formatting program, from one of the magazines, sticks an extra sector (up to 10 from 9) on each track, as does TWISTER; but it doesn't do anything with the sectors. Any help, as always, is appreciated. One quick note: throughout the article, Dave Small (he and Dan Moore wrote the programs) refers to TWISTER with a TOS extension, while the disk has a squeezed PRG file. Thanks. Jim Moore@NCSC.arpa
sansom@trwrb.UUCP (03/12/87)
In article <8703102314.AA10864@ncsc.ARPA> moore@NCSC.ARPA (Moore) writes: >Does TWISTER.PRG, published in this quarter's STart, work? I've had no problems at all with TWISTER (nice work Dave). I'm gonna add 82 track formatting this weekend. -Rich -- //////////////////////////////////////\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ /// Richard E. Sansom TRW Electronics & Defense Sector \\\ \\\ {decvax,ucbvax,ihnp4}!trwrb!sansom Redondo Beach, CA /// \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\/////////////////////////////////////
john@viper.UUCP (John Stanley) (03/17/87)
In article <8703102314.AA10864@ncsc.ARPA> moore@NCSC.ARPA (Moore) writes: > >Does TWISTER.PRG, published in this quarter's STart, work? [Background: the >program formats floppies such that each track has its sector numbers offset >by two from the previous track, so that double reads of a single track caused >by seek and settle times are eliminated]. It sure sounds like it should work, >but I don't notice any difference at all! > Jim, from my understanding, the advantages from Twister formatted disks comes when copying large files. When you copy many smaller files, the head must interrupt it's Twister enhanced read/write, go to the track and sector where the directory is held, do some processing, and then move back to the place where it was in the Twister sequence. This destroys the timing. Also if you have lots of smaller files spread across several tracks/sectors where there are gaps, thi will also' cause timing problems. To best see the difference copy a large** file to a twister disk and another disk. Then try reading/copying that file with any program that can copy/read the file at a -very- high rate. The twister disk will read so fast you won't beleive it... --- John Stanley (john@viper.UUCP) Software Consultant - DynaSoft Systems UUCP: ...{amdahl,ihnp4,rutgers}!{meccts,dayton}!viper!john