Andrei Popescu wrote: > Willie Wonka <[EMAIL PROTECTED]> wrote: > > > Binary Example > > 1,024 > > 1,048,576 > > 1,073,741,824 > > 1,099,511,627,776 > > [snipped] > > To try and sum up my point; > > Everytime you step *up* using a power of 10, you lose MORE when > > converting to Binary. > > > > IMHO; > > 1024 * 1024 = Correct > > 1024 * 1000 = Incorrect > > 1000 * 1000 = Incorrect > > > > I think much of the confusion stems from the numeric *starting* point. > > Perhaps I'm just Full_of_$Hit ...and I have been wrong before in my > > life :-) > > I did the calculations only for the TB/TiB case, but you have to redo > the calculation for ever given size. > > Real life case: my laptop has a 20GB HDD = 2000000000 B /1024 /1024 = > ~ 19.07 GiB => I lose ~ 903 MiB. > > For me this makes more logic, as there will never be a 20, 80, 200 GiB > HDD, they are all 20, 80, 200 GB. What real size they have, you have to > calculate for each one. Your rule is correct, but it doesn't tell me > what the size of a given HDD is. I concur; -- however (and I should refine my statement earlier, about HDD Manu's in general, as a *lie* - to perhaps *exaggerate*, or a similarly less harsh word), - your 20GB HDD actually size (contains) is more than 20 Billion Bytes (likely ~20,587,000,000 bytes). This just makes for unnecessary further confusion..here's an example using the 'hdparm' utility (which I'm sure you're familiar with);
e.g.; I have some 80GB HDDs here, which are actually 82,348MB -or- 78,533MiB ~$ sudo hdparm -I /dev/hda ... ... device size with M = 1024*1024: 78533 MBytes device size with M = 1000*1000: 82348 MBytes (82 GB) > > In this example, I'll use [Sector=512Bytes] and [Track=4096Bytes = 8 > > Sectors]. > > Data (File) that occupies more space than 1 sector (512Bytes), will > > fill up those sectors until the Track/Block/Cluster (8 sectors) is > > full, ...and a larger File will then overflow onto the next > > Sectors/Track, and so on -- this is merely a consequence of > > *contiguous* writing of data. > > You can't mix tracks and sectors with blocks/clusters. The former are > physical 'units' while the later are logical. I think I'll leave this part of the topic alone for now, since I need to brush up on my understanding of the 'physical' (CHS) vs 'logical' (LBA) differences, but indeed a *Track* in Linux seems to contain 63 sectors, as noticed again using 'hdparm' ~$ sudo hdparm -I /dev/hda .... Configuration: Logical max current cylinders 16383 65535 heads 16 1 sectors/track 63 63 -- CHS current addressable sectors: 4128705 LBA user addressable sectors: 160836480 LBA48 user addressable sectors: 160836480 .... > > Cylinders are ring-shaped, vertically aligned areas of the HDD - think > > of stacking doughnuts or rings; one on top of each other, the only > > difference (besides the obvious), is that no 2 stacks of > > cylinders/doughnuts/rings are the same physical size...yet they are > > stacked vertically (according to the platters). This all starts to get > > real *funky* once you start using LBA, instead of *phsyical* address. > And a track is one dough-nut. And because in reality the radius of the > dough-nut and hence also its length, the number of sectors/track is > variable. But the OS doesn't see this. The numbers are converted > inside the HDD logic and passed to the BIOS/OS as if the number of > sectors/track is constant. Otherwise a C/H/S address would make no > sense to the BIOS/OS. I'll accept that info for now... thanks; I'll digest it over time, and research a bit more, before again addressing this sub-topic ;) > > > The smallest physical unit is the sector which is always 512 B. > > > When you format a partition you divide it in allocation units. In > > *nix > > > they are called blocks, in MS clusters. > > > > Yes, I concur; > > but I'd refine it to *a group of sectors, which has a set size* > > perhaps. > > and that size is always 2^x * 512B where x is a positive integer value > (zero allowed). How big it can get depends on filesystem limitations. Yep ....Ok > Bye > Andrei I appreciated this dialog/dialogue :-) All I can think of now, because I'm hungry is (donuts/doughnuts/dough-nuts). Regards __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]