dillon@CORY.BERKELEY.EDU (Matt Dillon) (05/04/87)
DOS also (and this is something Bryce found out) reads ALL of the extended blocks for each file when you are doing a directory list. THERE IS NO REASON TO DO THIS! The file size is stored in the inode for that file.... why does DOS do this? PROOF: Intercepting the trackdisk device again, and getting a directory of a disk which contains the following: rwxd 0 DIR c rwxd 603373 aztec.bak.Z TOTAL: 603373 Now intercepting all DoIO() and SendIO() operations Device__ Cmd_ Len_____ trackdisk.device READ 200 70c00 Blk#: 902 (Trk 41 Cyl 0) trackdisk.device READ 200 71000 Blk#: 904 (Trk 41 Cyl 0) trackdisk.device READ 200 71200 Blk#: 905 (Trk 41 Cyl 0) trackdisk.device READ 200 71400 Blk#: 906 (Trk 41 Cyl 0) trackdisk.device READ 200 71800 Blk#: 908 (Trk 41 Cyl 0) trackdisk.device READ 200 71a00 Blk#: 909 (Trk 41 Cyl 0) trackdisk.device READ 200 71c00 Blk#: 910 (Trk 41 Cyl 0) trackdisk.device READ 200 71e00 Blk#: 911 (Trk 41 Cyl 0) trackdisk.device READ 200 72000 Blk#: 912 (Trk 41 Cyl 0) trackdisk.device READ 200 71600 Blk#: 907 (Trk 41 Cyl 0) trackdisk.device READ 200 72200 Blk#: 913 (Trk 41 Cyl 1) trackdisk.device READ 200 72400 Blk#: 914 (Trk 41 Cyl 1) trackdisk.device READ 200 72600 Blk#: 915 (Trk 41 Cyl 1) trackdisk.device READ 200 72800 Blk#: 916 (Trk 41 Cyl 1) trackdisk.device READ 200 72a00 Blk#: 917 (Trk 41 Cyl 1) trackdisk.device READ 200 72e00 Blk#: 919 (Trk 41 Cyl 1) trackdisk.device READ 200 6e200 Blk#: 881 (Trk 40 Cyl 0) trackdisk.device UPDATE 238134 0 Blk#: 0 (Trk 0 Cyl 0) trackdisk.device NON+ 0 0 204808 Blk#: 4132 (Trk 187 Cyl 1) Restoring intercept vector 19 operations monitored -Matt