All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 6 posts ] 
Author Message
 Post subject: What is the factor/formula?
PostPosted: September 27th, 2018, 9:38 
Offline
User avatar

Joined: May 13th, 2010, 11:17
Posts: 2370
Location: Kuwait
Dear Experts,

One question came to my mind once about How HDD/OS writes, i was thinking about How or Who decides this Specific File (for example) will be written to that specific sector?
Anyone knows?

is it based on a formula/OS/FS? or how its been calculated?

sometimes you see the HDD is filled with data from the beginning then Empty Space (zeros) then again data

i was wondering how?

Thank you :wink:

_________________
Kuwait Data Recovery - UNIX GTC
The only reason for time is so that everything doesn't happen at once. By: Albert Einstein


Top
 Profile  
 
 Post subject: Re: What is the factor/formula?
PostPosted: September 30th, 2018, 2:46 
Offline
User avatar

Joined: May 13th, 2010, 11:17
Posts: 2370
Location: Kuwait
None? :heeey:

:shock:

_________________
Kuwait Data Recovery - UNIX GTC
The only reason for time is so that everything doesn't happen at once. By: Albert Einstein


Top
 Profile  
 
 Post subject: Re: What is the factor/formula?
PostPosted: October 2nd, 2018, 12:14 
Offline

Joined: August 13th, 2016, 17:10
Posts: 80
Location: Vienna, Austria
That formula is well hidden inside the filesystems (or more specifically the filesystem implementations). Every filesystem has its own formula. And that's the main job of a filesystem to decide where things go. For some filesystems there are even tools like defragmentation which can change the position afterwards.


Top
 Profile  
 
 Post subject: Re: What is the factor/formula?
PostPosted: October 2nd, 2018, 14:43 
Offline
User avatar

Joined: December 19th, 2006, 8:49
Posts: 9985
Location: Portugal
And to add to this the drive itself will decide what LBA (sector) will belong to each physical location ...

Meaning the file system will tell what LBAs a file will be stored to and the drive itself will "translate" those LBAs to physical place on platter.

_________________
1Q9xrDTzTddUXeJAFRn37aqh1Yr6buDCdw - (Bitcoin Donations)
paypal.me/Spildit - (PayPal Donations)
The HDD Oracle - Platform for OPEN research on Data Recovery.


Top
 Profile  
 
 Post subject: Re: What is the factor/formula?
PostPosted: October 3rd, 2018, 2:32 
Offline
User avatar

Joined: May 13th, 2010, 11:17
Posts: 2370
Location: Kuwait
sourcerer wrote:
That formula is well hidden inside the filesystems (or more specifically the filesystem implementations). Every filesystem has its own formula. And that's the main job of a filesystem to decide where things go. For some filesystems there are even tools like defragmentation which can change the position afterwards.



Spildit wrote:
And to add to this the drive itself will decide what LBA (sector) will belong to each physical location ...

Meaning the file system will tell what LBAs a file will be stored to and the drive itself will "translate" those LBAs to physical place on platter.


Any Base/Ref. to all of this? prefer if Technical Doc. not some sort of essay written by some dump or none-tech. person.

Am asking in general because am doing some research about something else, but this Question came to my mind

I tried reading many articles/docs none was helpful..

Thank you

_________________
Kuwait Data Recovery - UNIX GTC
The only reason for time is so that everything doesn't happen at once. By: Albert Einstein


Top
 Profile  
 
 Post subject: Re: What is the factor/formula?
PostPosted: October 3rd, 2018, 4:49 
Offline

Joined: August 13th, 2016, 17:10
Posts: 80
Location: Vienna, Austria
In case of Linux filesystems, you can get the sourcecode on www.kernel.org :

For FAT:
https://git.kernel.org/pub/scm/linux/ke ... 9-rc6#n263

For EXT2:
https://git.kernel.org/pub/scm/linux/ke ... =v4.19-rc6
https://git.kernel.org/pub/scm/linux/ke ... 9-rc6#n259


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 6 posts ] 

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: Google Adsense [Bot] and 30 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group