How important is 64K block size

[msmith8228]

Can anyone explain to me how important 64K block size is for recording or playing back HD material.

I have numerous 250gig disks (a total of six) on my HD Sage setup and just realized that they are all formated with 4K disk block / sector size. The system works quite well with only ocasional stuttering.

Fixing this issue (changing to 64K block size) will be a real pain.

Comments?

[Opus4]

I believe it to be very important. My understanding is that once the file is fragmented on the 4K cluster size, it can become impossible for the drive to seek to the next file portion faster enough to keep up with the data throughput needed for recording or playback (and that's just for SD material), so there will be data lost while trying to record or stuttering during playback. This is usually not an issue with 64K clusters - I won't say it is impossible for fragmentation to be an issue with 64K clusters, but it is much less likely. I haven't defragged my recording drives in over a year & don't plan to do so.

There are utilities that can change the cluster size w/o reformatting. Partition Magic can do it & so can a utility from Acronis, among possible others. Lately, I would go with Acronis.

- Andy

[malbec]

Agree with Opus, but from past experience...if it ain't broke, don't fix it.

[mcbinder]

Originally Posted by malbec

Agree with Opus, but from past experience...if it ain't broke, don't fix it.

But he said it was broke(n) and stuttering, so a fix is in order.

When I did this I just copied all of my content off to another drive and re-formatted to 64k, then copied it back (directory structure and all).

He said there were numerous drives, so finding space should not be too much of a problem. Or delete temporary shows (after watching them stuttering) and delete. Then reformat.


Mike

[malbec]

Oops, missed that, sorry.

[mazakmaster]

curiuos, if 64k is that much better why isnt it the default? woudnt it be better to run all computers for any application with this cluster size?

[bcjenkins]

Originally Posted by mazakmaster

curiuos, if 64k is that much better why isnt it the default? woudnt it be better to run all computers for any application with this cluster size?

It would waste space. The reason it works so well for recordings is because the files are so large.

B

[blade]

Originally Posted by mazakmaster

curiuos, if 64k is that much better why isnt it the default? woudnt it be better to run all computers for any application with this cluster size?

It's not better, just better for very large files. You should still leave your OS drive formated to 4k.

Say you have a 1k file. If your drive is formated to 4k it's going to take up 4k of space. On a disk formated to 64k that same file is going to take up 64k. Regardless of the file size it's going to be stored in a multiple of 4 k, 64k, or whatever the drive is formated to. So if the file was 65k it would take up 68k or 128k.

It's impossible for 64k to become as fragemented as 4k can get.

[hemicuda]

Originally Posted by Opus4

There are utilities that can change the cluster size w/o reformatting. Partition Magic can do it & so can a utility from Acronis, among possible others. Lately, I would go with Acronis.

- Andy

I vote against PM as well.

Thanks to PM a few yrs ago I lost an 18gig data drive (back when that was a big deal) while trying to merge 2 volumes w/ differing cluster sizes. PM tried to rework one of them to match and failed miserably. Best I managed to recover was a listing of the filenames on the partition. Least I know what I HAD. YMMV

[mdnttoker]

I'm finally getting around to changing the block size on one of my HD's.

I've previously used a 64k block size one one HD, but now running Paragon Disk Manager, I have the option of moving to 128k.

Has anybody had any experience with 128k? Is it any better / worse than 64k?

[m1abrams]

Originally Posted by mdnttoker

I'm finally getting around to changing the block size on one of my HD's.

I've previously used a 64k block size one one HD, but now running Paragon Disk Manager, I have the option of moving to 128k.

Has anybody had any experience with 128k? Is it any better / worse than 64k?

I did not know NTFS supportted 128k blocks?

[mdnttoker]

Originally Posted by m1abrams

I did not know NTFS supportted 128k blocks?

Neither did I. This is on a 1.5TB disk...maybe size matters?

Anyway, the 128k scared me, so I just stuck with 64k (since I already had recordings on the drive, and didn't want to mess 'em up. otherwise, I would have experimented!)

[stanger89]

Fat and Fat32 support up to 256k clusters, but I can't find anything that says NTFS supports larger than 64k.

[paulbeers]

Originally Posted by mdnttoker

...maybe size matters?

Size always matters!

Sorry I couldn't help it.

[dotheDVDeed]

Probably a stupid question but here goes...
Any way to check in windows xp how a hard drive was formatted?
I can't remember if I did or not.

[Greg]

Originally Posted by Opus4

I believe it to be very important. My understanding is that once the file is fragmented on the 4K cluster size, it can become impossible for the drive to seek to the next file portion faster enough to keep up with the data throughput needed for recording or playback (and that's just for SD material), so there will be data lost while trying to record or stuttering during playback. This is usually not an issue with 64K clusters - I won't say it is impossible for fragmentation to be an issue with 64K clusters, but it is much less likely. I haven't defragged my recording drives in over a year & don't plan to do so.

There are utilities that can change the cluster size w/o reformatting. Partition Magic can do it & so can a utility from Acronis, among possible others. Lately, I would go with Acronis.

- Andy

Does the hard drive have a buffer to reduce the chance of stuttering due to excessive search time because of a fragmented drive? If the buffer empties due to excessively long searches then I could see stuttering.

Greg

[stanger89]

Originally Posted by dotheDVDeed

Probably a stupid question but here goes...
Any way to check in windows xp how a hard drive was formatted?
I can't remember if I did or not.

chdksk.exe will tell you.

[mr_lore]

See setup below, I've got all kinds of HD flying all over the place and not a 64k cluster in sight, never had any issues.

[stevech]

Also, I think the I/O's per second reduces with the use of 64K blocks for large files.

[GKusnick]

Originally Posted by Greg

Does the hard drive have a buffer to reduce the chance of stuttering due to excessive search time because of a fragmented drive? If the buffer empties due to excessively long searches then I could see stuttering.

Yes, hard drives have buffers, which can help smooth out occasional hiccups. But if a file is fragmented to the point where the average fragment contains fewer milliseconds of video than the average seek time between fragments, then buffering can't make up the difference (short of buffering the entire file, and no drive has a buffer that big). That's the point of large clusters: to keep the fragment size well above that seek-time threshold, no matter how fragmented the file gets.