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Greg Freemyer wrote:
It is time for you to enter the 21st century in respects to disk geometry.
---- Greg, stop showing your ignorance. The LBA still corresponds to CHS *internally* -- just that the nums are internal to each HD.
For at least the last decade the linear density of sectors is typically constant over the whole platter. Since you know circumference of a circle is PI * D, a track 3 inches from the center holds 3x the sectors as one 1 inch from the center. That means number of sectors per track isn't even a constant for a modern drive.
---- Wrong. Modern HD's have been divided into zones for the past 15+years... Modern HD's have almost 1 zone/TB, but you can see a most modern examople at: http://media.bestofmicro.com/E/N/362111/original/throughput-diagram-wd4001FA... Latest 4TB HD... That isn't a smooth curve -- Each notch is a zone.. Across each zone the number of sectors is constant. Very odd on that graph... notice as some have noted the first 50-100GB are slightly lower than just past the 100GB mark -- for READS... writes seem to be very smooth but likely due to internal disk buffering...
Fyi: both modern windows and linux align to 1MB boundaries with no concern how that aligns with tracks.
---- Depends on what disk partition tool you use, but I don't know of any that use MB. The default display in fdisk:...sd Device Boot Start End Blocks Id System /dev/sdc1 63 25398764 12699351 83 Linux /dev/sdc2 25398765 42009974 8305605 83 Linux /dev/sdc3 * 42009975 44130554 1060290 83 Linux Shows POSIX standard 512 byte sectors. parted.. Number Start End Size Type File system Flags 1 32.3kB 13.0GB 13.0GB primary xfs type=83 2 13.0GB 21.5GB 8505MB primary xfs type=83 3 21.5GB 22.6GB 1086MB primary xfs boot, type=83 4 22.6GB 146GB 123GB extended type=05 5 22.6GB 31.2GB 8595MB logical linux-swap(v1) type=82 6 31.2GB 47.3GB 16.1GB logical xfs type=83 7 47.3GB 58.0GB 10.7GB logical xfs type=83 8 59.1GB 145GB 85.9GB logical type=83 Hmm....looks like kB is the lowest unit well...nope... (parted) help unit unit UNIT set the default unit to UNIT UNIT is one of: s, B, kB, MB, GB, TB, compact, cyl, chs, %, kiB, MiB, GiB, TiB default is 'compact'... As for my other two sd's, they both start at 17.4kB -- that's not a 1MB boundary either... it's actually 34 sectors -- I guess thats a gpt size -- and boot drive is sdc... starting at the 63 sector Looking at the # blocks/partition and dividing by 2*1024*1024 (sectors->MB): fdisk -l /dev/sdc|cut -c41-49|grep -P '^\s*[0-9]+$'|while read secs;do printf "%10d %s\n" "$secs" "$(pcalc "$secs/(2*1024*1024)"|grep -P '= \d')" done 12699351 = 6.05552244186401 8305605 = 3.96042108535767 1060290 = 0.505585670471191 120278655 = 57.3533320426941 8393931 = 4.00253820419312 15735636 = 7.50333595275879 10490413 = 5.00221872329712 83883366 = 39.9987058639526 ---- I would say those are track aligned -- That's a 21st century 15K SAS drive. MB alignment?... I don't think even windows is that dumb. Track alignment is still an issue -- ask anyone running RAID -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org