FAT32 and clusters

A forum for general AmigaOS 4.x support questions that are not platform-specific
Post Reply
User avatar
Mrodfr
Posts: 29
Joined: Wed Jul 06, 2011 5:29 pm

FAT32 and clusters

Post by Mrodfr »

Hello,

I have optimized my 16go USB stick by changing the clusters. Because the speed copy on PC change from 15 mb/s to 30 mb/s.


from the documentation:

This mountlist FSSM environment value can is really treated
as "FAT physical blocks" per "FAT sector" and be set to
a power of 2 to enforce a specific FAT sector size of 512,
1024, 2048, 4096 bytes, when multiplied with the physical
sector size of the underlying disk.

I'm using a 512 block on the key but a bigger cluster size.

The result is a requester who said:

volume has broken clusters geometry. can't mount it ?



- Please, first, add more clusters support for the next update.

- Remember me the clusters supported on AOS4 actually, thanks.
User avatar
ZeroG
Posts: 124
Joined: Sat Jun 18, 2011 11:31 am
Location: Germany

Re: FAT32 and clusters

Post by ZeroG »

You tried to mount a USB stick using a different cluster size, but don't re-formated it using that changed mountlist?
User avatar
Mrodfr
Posts: 29
Joined: Wed Jul 06, 2011 5:29 pm

Re: FAT32 and clusters

Post by Mrodfr »

Hello,


NO. I have formatted, using a PC tool (I think FAT32formatter),my 16go USB key. I could said more tomorow at job office. the tool is installed on the job office PC ;-)

the tool test the good cluster for the size of the FAT32 medias. I have increased the copy speed from 15mb to 25mb with this tool and I have finally formatted my USB key with this tool with the recommended high clusters.

Unfortunately, the key isn't recognized more on the amiga.

I have made that recently that mean I'm not sure the key work with update2.


More support of the size of clusters (FAT) will increase the speed copy.
User avatar
tonyw
AmigaOS Core Developer
AmigaOS Core Developer
Posts: 1479
Joined: Wed Mar 09, 2011 1:36 pm
Location: Sydney, Australia

Re: FAT32 and clusters

Post by tonyw »

I think you can assume that CrossDOS only supports the standard cluster size. It is unlikely to be expanded.
cheers
tony
xenic
Posts: 1185
Joined: Sun Jun 19, 2011 12:06 am

Re: FAT32 and clusters

Post by xenic »

tonyw wrote:I think you can assume that CrossDOS only supports the standard cluster size. It is unlikely to be expanded.
I doubt if cluster size is the problem anyway. I ran some quick copy tests with 8 files totaling 116 MB. Here are my results with Update3 installed:

Copy from Ram: to USB mem stick formatted with FAT= 280 seconds
Copy from USB mem stick formatted with FAT to Ram:= 13 seconds
Copy from Ram: to USB mem stick formatted with SFS= 25 seconds
Copy from USB mem stick formatted with SFS to Ram:= 12 seconds

As you can see the FAT write speeds are unbelievably slow. My test with an SFS formatted mem stick indicates that the problem isn't with USB; the speed is far greater than I got with USB 1.1. Something appears to be wrong with CrossDosFilesystem because the write speed are comparable to USB 1.1 instead of USB 2.
AmigaOne X1000 with 2GB memory - OS4.1 FE
User avatar
Hypex
Beta Tester
Beta Tester
Posts: 645
Joined: Mon Dec 20, 2010 2:23 pm
Location: Vic. Australia.

Re: FAT32 and clusters

Post by Hypex »

Is CrossDOS using any cache buffers? Can these be specified?
User avatar
Mrodfr
Posts: 29
Joined: Wed Jul 06, 2011 5:29 pm

Re: FAT32 and clusters

Post by Mrodfr »

The support of the clusters should be expanded.

I could double the speed read and write on my 16go USB stick (FAT32 formatted).

Thanks to previous poster about speed test with FAT and SFS. I know It's a FAT32/CrossDOSfilesystem only now).

FAT32 support should be expanded to share datas easily with others platforms !!!!!
Post Reply