[alcimedes]

So I've got some drives that are being used to back up various machines at work. They only contain backup files on them, which are huge files containing all the data.

These drives have approx. 20 or so files on them, but the files are about 40 GB on average. So what I'd like to do is reformat the drives to have a larger default block size, as the current 512byte is really quite small. Anyone know of a utility that will do this in OSX? I don't mind paying for one, but google searches turned up nothing for me.

Oh yeah, and whatever I format them with would have to be able to allow them to be in a striped RAID. Not sure if OSX reformats a drive's default block size when you RAID them though. Anyone know?

[Brad]

I don't think you can do this with HFS or HFS+. HFS divides the drive into x number of blocks. The bigger the drive, the bigger the blocks.

I'm not sure how UFS or other formats handle it.

[Barto]

Slightly off topic: Apple should use Reiser. Best. File system. Evar.

[Kickaha]

Originally Posted by Brad I don't think you can do this with HFS or HFS+. HFS divides the drive into x number of blocks. The bigger the drive, the bigger the blocks. I'm not sure how UFS or other formats handle it.

HFS did it that way, HFS+ is adaptive - if the drive is large enough that the default number of blocks would create blocks larger than 4k, it sets up more blocks. ie, 4k is the largest block you can have.

[ThunderPoit]

out of curiosity, why do you want larger block sizes?

[Kickaha]

Yeah, I've been wondering that too... seems weird to me.

[Paul]

so the disk is more efficient. Since all the files are going to be huge it would save a small percentage (but still significant) of each file. Instead of a 40 gb file taking up X million blocks, divide that number by like 500 or something.

This is all me talking out my ass, but it makes sense to me...

[ast3r3x]

Originally Posted by Paul so the disk is more efficient. Since all the files are going to be huge it would save a small percentage (but still significant) of each file. Instead of a 40 gb file taking up X million blocks, divide that number by like 500 or something. This is all me talking out my ass, but it makes sense to me...

How would that help though? Sorry, I always was under the impression that it was better to have smaller blocks.

[Gargoyle]

Actually, the disk would be less efficient. But, it would probably fragment less (although it probably won't do that anyway with 40G files), and it will be a bit faster.

I did a really good module back in uni about multimedia stuff and how different file systems were better for different types of files. IMG - that was almost 7 years ago!!! I'm getting old.

[alcimedes]

it would, in theory be approx. 3%-5% faster for read/writes.

it should also fragment less.

as it is now, when i make a full backup of the drive from one to another, it takes 7 hours. (over firewire). if i could shave off 20 min. of that it would be nice.

[ThunderPoit]

there was a program, waaaay back in the day when 8.1 and HFS+ was released, called drive + or drive plus. anyway, it allowed you to convert your drive from hfs to hfs+ w/o reformatting, and it allowed you to choose your block size. im not sure where to find this program anymore, a google search could turn something up tho.

[ThunderPoit]

ahh, found it, i was way off, check out these guys, not sure how well you can select block sizes tho: http://www.alsoft.com/

[ast3r3x]

Originally Posted by ThunderPoit ahh, found it, i was way off, check out these guys, not sure how well you can select block sizes tho: http://www.alsoft.com/

I remember this! It required you to have enough free space though. So I took my 2.3GB HD...or maybe it was 3.4GB, either way, and back some stuff on on like 10 zip disks, and went to town. I was so worried it would mess up, or like power would fail while doing this. But I was happy in those days that it let me regain 600MB.

[alcimedes]

i'll take a look at it. i wonder if i set the block size, it it will resize them when i use the OSX disk tool to make the disks into a RAID. i'll play around and find out.

i've got 4 250GB drives set as 1 drive in a RAID. the files on there now take up about 600 - 700 GB, so i might have to move a few before trying the tools out. the other problem is that they're on a G5, which means no OS9 booting. actually, i don't think any of my computers will boot into 9 now, but i'll find a workaround.

[ast3r3x]

Have you looked for a unix program to format drives. I'd imagine one exists, and would give you very much control...I mean it's f'n unix.

[ThunderPoit]

ahhh, crap, what kind of raid? if its just a software raid set up w/ disk util, it wont work as this program is OS 9 only and OS 9 cant see a raid :/

[alcimedes]

yeah, it's a software raid in OSX. i'm saving up from my work budget to afford a real RAID, but this is all i have access to for now. i'll get by if i can't reformat it, just thought i'd ask.