Partitioning problem ,showing double the data size ....

[mudh]

I wanted to partition my 1TB hard disk with disk utility , all I had in that disk was 400 GB data so I wanted to partition it into two partitions of 500MB each , I successfully dragged the slider to adjust sizes and started the process, unfortunately there was power cut and I had to restart the comp after which now it show a full partition of 999GB and almost entire partition barring a few MBs is blue , that is , it is showing that almost the entire drive is full with data which is not true, so obviously when I try it doesn't partition and all tabs on the partition page are greyed..... while trying to partition I get this error too :

Partition failed with the error:

Couldn’t modify partition map because file system verification failed.

How should I correct it now ......I don't have any recovery data on time machine

?

 

[Cory Cooper]

Hello and welcome.

First off, a few questions for you:
-Which model Mac - a Mac Pro I assume?
-Which version of OS X - looks like 10.9.x Mavericks?
-That drive is a WD Blue 1TB, correct?
-Is there a specific reason for partitioning the drive?

IMPORTANT - Do you have a backup of the data on the drive you resized?

C

 

[mudh]

Thanks for your reply , .....Yes , Mac pro 2012 all specs you mentioned are correct ,
Yes the reason of partitioning the drive was that I wanted to use half for one OS and another for another OS version due to compatibility limitations of certain required softwares and plugins.
No now I don't have the back up of this drive in its unpartitioned previous state , but after this weird thing happened , I knew I might have to try some risky trial and error so I have cloned this drive in its current state , it is fully functional and I am working without any problem with it besides this false size issue and not being able to partition.

I am thinking that this size that it is showing is misleading but may be in the process of partitioning , some duplicated files were created or something , is there a way of knowing why is it showing that size or a process like defragmentation in windows so that it re assesses the data and shows it's real size ?

 

[Cory Cooper]

Thanks for the additional information.

It sounds like the original partition you tried to create didn't finish and failed due to the power cut/restart. That may be why the size is not what you had originally set it to. The blue it is showing is just the indicator for which partition is selected, not how much data is on it. The smaller partition should turn blue if you click on it, and the larger partition should turn white.

-Do both partitions mount in Finder, and are their sizes the same as in Disk Utility?
-I doubt it is still in the process or partitioning, if it did't finish before the power cut.
-It sounds like it did partition somewhat, and your files are intact, since it and the clone are working normally.

Disk Utility doesn't show fragmentation like Windows, and it doesn't have a defrag option. Some third-party apps do, but it really isn't needed these days due to drive speed and efficiency. Also, the Mac OS X Extended (HFS+) file system automatically defrags files when the system is idle.

Since you now have a clone/backup of the drive, I think the best bet would be to erase it and try partitioning it again. You can then clone your data back to the new partition, and install the other OS on the second.

C

 

[mudh]

Thank you so much for your reply , I am a little confused , since my weird drive is showing a size of almost 1 TB instead of 400 GB , obviously the cloned drive is also of the same size , if I try to clone date back to my new partition of 500GB , how will clone more than 900GB size fit into a 500 GB partition ?..... or is there a way to make a recovery backup other than cloning where only system files with all softwares are backed up and that back up would be smaller in size ?

 

[mudh]

I hope I have not asked anything too stupid ha ha , what I am saying is if I copy paste all the files of Machintosh HD including hidden files and paste in an an empty partition does it become a new bootable hard disk ?