On Jan 5, 2009, at 9:50 AM, Hunter Fuller wrote:
> > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > 2009/1/5 D Stubbs : >> I am trying to get my head around this concept - that a partition >> is not a >> partition. Tried googling "Understanding Partitions" and "What is a >> Partition". All I found were basic descriptions of the fact. Even >> found a >> recent blog by Dan Knight on his partitioning: >> http://lowendmac.com/musings/08mm/partition-your-hard-drive.html >> But I am no further in understanding what is actually happening. > > The post by Charles (I think it was) is incorrect. The disk is > partitioned in this manner: > Say you have multiple platters in a drive (the most common) and you > have an 80 GiB disk. > We will say it has four platters for simplicity. > When you partition it, let's say you create 2x 40 GiB partitions. That > means the data in partition one will be stored on platters 1-2 and the > data in partition two on platters 3-4. MAYBE --- depends on the manufacturer. They can do it any way they want to, because it doesn't matter to the Operating System. For this to be true, the Numbering Scheme for sectors needs to start at the beginning of Platter #1 Side #1 (yes, they do use both sides at times,), then Platter #1 Side #2, then P #2, S#1, ... When in actuality, the usual numbering system follows the P #1, S#1, Cylinder #1, P#1, S#2, C#1, P#2,S#1,C#1, P#2,S#2,C#1, P#3,S#1,C#1,P#3,S#2,C#1, then after all the platter sides are used, start again at platter #1S#1,C#2, ... The reason being that it is faster to 'change the W/R head, than it is to physically move the W/R head to a different cylinder. > Of course due to overhead, the break will not exactly be on the break > in the platters (some of partition one might spill into platter 3). > That is fine. One platter cannot fail. They are all on the same > spindle motor and the same read head arm. Read heads are the only > thing different between the platters and those > 99.999999999999999999999999% of the time don't fail. I've never seen > that happen and I've seen a lot of disks fail (unfortunately). > I think the usual failure mode these days, is a surface deformity of some sort. Chuck D. >> I suppose it is some kind of 'virtual directory'? >> What makes no sense yet to me is how, say partition #3 could go >> bad, and not >> the others - if it they all bunched together. >> But then this question may be beyond the scope of the present >> discussion - >> maybe someone knows of a url that is 'Understanding partitions 101 >> for the >> average idget'? >> Thanks for all the help, I have decided on 3 partitions. >> Del >> >>> >> > > > > - -- > - -hackmiester --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed Low End Mac's G3-5 List, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/g3-5-list?hl=en Low End Mac RSS feed at feed://lowendmac.com/feed.xml -~----------~----~----~----~------~----~------~--~---
