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NTFS 512 byte cluster size. Can't resize C: to 4kb

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September 20, 2006 7:58:34 PM

I have two physical drives, C and D. PC boots off C and run XP Pro. I recently used CONVERT to convert filesystem from FAT32 to NTFS but found that the cluster size is 512 bytes and not the optimal 4kb. I bought PartitionMagic 8 as it has an option to resize NTFS cluster sizes.

After running "chkdsk /f" on both drives (they had problems to be fixed) my D drive resize worked fine.

However, although the process completed 100% on the C drive, I got error 728. Contacted Symantec support who told me that they don't recommend changing the cluster size on the primary partition. So I'm stuck with a 512 byte cluster size which is making my PC very noticeably slower.

I really don't want to reformat C: to resolve the problem. I also don't want to admit defeat, in a sense, and convert back to FAT 32 to get the speed back.

I'd _thought_ I could maybe make D the primary drive, even although it wouldn't have an OS on it (I'd boot of the PartitionMagic floppy) and that would allow me to resize the cluster size on C before I switch the drives around again.

The thing is, I simply don't know how to do it.

If anyone has advice including alternatives then I'd be most appreciative as the slowness is driving me mad.
September 20, 2006 8:56:13 PM

If you mean kilobytes, the 512 bytes is 4kb.
September 20, 2006 9:39:13 PM

Quote:
If you mean kilobytes, the 512 bytes is 4kb.


I'm sorry but I don't understand. 512 bytes is 0.5 kb.

The cluster size is 512 bytes but I want to change it to 4096 bytes.

Everything I'd read, prior to converting to NTFS suggested that the cluster size may default to 512 bytes depending on circumstances and that's what's happened in my case.
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September 20, 2006 9:41:01 PM

There are switches under NTFS that allow one to set the cluster size to different values. The smallest is 512 bytes. While 512x8=4096 bits, I don't think this addresses the question.

It's sort of like trying to move your research notes from post-it notes to regular sized paper by rubbing the posty note on the regular paper. While it might work in theory, the practical problems will kill any benifits you might have gained with the attempt. Sorry but I've found that by the time you find out that the options you've gathered don't work you will have been able to wipe and reload the primary drive.

Why don't you just save a files and settings transfer wizard output as well as any backups you need to the D: drive and start over on C: ?
September 28, 2006 7:48:35 PM

Quote:
I have two physical drives, C and D. PC boots off C and run XP Pro. I recently used CONVERT to convert filesystem from FAT32 to NTFS but found that the cluster size is 512 bytes and not the optimal 4kb. I bought PartitionMagic 8 as it has an option to resize NTFS cluster sizes.

However, although the process completed 100% on the C drive, I got error 728. Contacted Symantec support who told me that they don't recommend changing the cluster size on the primary partition. So I'm stuck with a 512 byte cluster size which is making my PC very noticeably slower.


If you cannot get the resize to work you might try the steps I have compiled at http://lila.godel.com/html/ntfsinfo.htm for resizing clusters on NTFS partitions in versions of partition magic prior to 8.0.
September 29, 2006 10:03:38 PM

Quote:
If you cannot get the resize to work you might try the steps I have compiled at http://lila.godel.com/html/ntfsinfo.htm for resizing clusters on NTFS partitions in versions of partition magic prior to 8.0.


Ran "compact" and PM rebooted PC to start conversion to FAT32 but gave up after discovering too many errors.

"compact" reported it had uncompressed 41 files. I guess there's no way of knowing what they were so I can recompress them is there?

Regards
September 29, 2006 11:09:13 PM

Quote:
If you cannot get the resize to work you might try the steps I have compiled at http://lila.godel.com/html/ntfsinfo.htm for resizing clusters on NTFS partitions in versions of partition magic prior to 8.0.


Ran "compact" and PM rebooted PC to start conversion to FAT32 but gave up after discovering too many errors.

"compact" reported it had uncompressed 41 files. I guess there's no way of knowing what they were so I can recompress them is there?

Regards

No you can't tell, however it is worth noting that Windows compresses all folders in C:\Windows in which the first character of the file name is a dollar sign. These folders contain backups of files that Windows makes when new service packs or patches are installed to allow for the items to removed in Add or Remove Programs.
September 30, 2006 12:06:08 PM

I reckon I had more than 41 such "c:\windows\$*" directories and there were a lot of subfolders and files beneath them but I've started compressing them all. I notice they change to a blue font in Windows Explorer but can't recall seeing them blue or black before.

Thanks for the advice.
November 14, 2006 10:05:11 PM

Thought I'd summarise what happened in the end.

Partition Magic wasn't able to do the job as it can't change the cluster on the primary partition. Bought Acronis Disk Director as it says it can. though it kept refusing to. Support said to make some space available but that didn't help.

Decided to convert BACK to FAT32 using Partition Magic which supports the conversion but it just totally screwed my hard disk. I had to reinstall Windows XP which has the benefit that the PC is a lot "lighter".

The moral: backup, backup, backup!!! Of which I had plenty.

Curiously, the Win XP install has a left a 8GB unapportioned partition on my hard disk. I didn't ask for it to be done. Is it due to the natural boundary of formatting the hard disk as NTFS? The cluster size is now 4KB and the PC hums along a lot, LOT better than the 512 byte cluster size.
November 14, 2006 11:07:44 PM

Quote:
Thought I'd summarise what happened in the end.

Curiously, the Win XP install has a left a 8GB unapportioned partition on my hard disk. I didn't ask for it to be done. Is it due to the natural boundary of formatting the hard disk as NTFS? The cluster size is now 4KB and the PC hums along a lot, LOT better than the 512 byte cluster size.


Not sure, about 8GB, but I have heard about 8MB being unpartitioned as detailed at http://mike-tech.com/article.php?gif=winxp&article=168.
November 15, 2006 6:47:07 PM

Quote:


Not sure, about 8GB, but I have heard about 8KB being unpartitioned as detailed at http://mike-tech.com/article.php?gif=winxp&article=168.


Actually you are correct. Have a look yourself but the link you supplied refers to 8MB.

Next question, arising from the link, is what's a dynamic volume?

And can I just merge the 8MB back into my C drive using Acronis?
November 16, 2006 9:51:25 PM

Quote:

Yes you can just merge the 8MB back in if you never want to have dynamic disks.


That was a good write-up! That said, not quite sure if it answers the question "do I want dynamic or basic disks?". I suspect I don't want dynamic because I've gone this long without it.
a c 126 G Storage
March 21, 2010 1:51:17 PM

If you want your partition to be optimal, re-create it. Converting stuff usually means you have performance disadvantages; just like when you convert Ext3 into Ext4. I can imagine this exists for FAT32->NTFS too.

You shouldn't have used FAT in the first place.
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