CWB OS3.9 and Large Disk Support

[fitzsteve]

Herro!

Sorry if we're going over old ground here, I just wanted to clear this in my mind.

If I'm using CWB OS3.9 that paches the SCSI on the double boot it already has large disk supprt right?

But is this the one thats limited to 8gb?

I've setup a HDD (and this is where it gets interesting) its a 40gb IDE HDD but I've set it up with 3x SFS Partitions 500mb SYS: 3gb Work: & 3.7gb Games: this is because I though there was that 8gb limit.

But 'wait for it' there is a further twist... This is connected to my BlizzardPPC SCSI via a SCSI-IDE adapter so I'm not sure if the patched SCSI even applies here, does the Blizzard SCSI already support large drives?

Am I right or am I just making all this up in my head!

Its all working fine by the way...

[thomas]

4GB limit applies to all devices when using an unpatched file system. 8GB limit applies to the unpatched internal scsi.device when using a scsi-cappable file system. No limit applies if both scsi.device and file system are patched.

BlizzardSCSI supports TD64 and SCSI, so what you want to use is either SFS, PFS3 or FFSTD64. OS 3.9's FFS can be used, too, but it limits the boot partition to 4GB.

BlizzardSCSI + SFS or PFS3 is the best combination you can get, because already at boot time no limits exist for partition size and location. (Except the partition size limit of the file system which is 128 GB for SFS and 106 GB for PFS3.)

[fitzsteve]

Thanks Thomas for clearing that up

I understand that patching theoretically allows the Amiga to use a disc of any size, and that using SFS limits partition size to 128mb.

Can I use SFS without SCSI? I'm guessing, to have a boot partition of 4GB, and then split the remaining space into 128GB partitions.

My plan is to use IDE to connect a 128GB drive to my A4000 until I can both find and afford a Cyberstorm 060 with SCSI kit, which I will then use the SCSI instead.

That's a point. Can an IDE drive be converted to SCSI? I have never used SCSI, and am therefore not au fait on the subject.

I know its a lot to ask in one go, but I'm not entirely sure which questions I should be asking.


Kind regards,
Nick

[thomas]

"scsi.device" is a generic driver name for accessing harddrives. In an A1200 and A4000 "scsi.device" refers to the internal IDE port. It's called "scsi.device" for compatibility, but it is IDE. So yes, surely you can use SFS without SCSI.

I don't know how far the patches of CWB reach. You need this patch (or something newer if that exists) to get LBA48 support. You need LBA48 to access harddrives larger than 128 GB.

Wow! Thanks for all your help Thomas!

One more thing, have you tried using a 128GB (or similar capacity) drive on a similar spec Amiga to mine? (A4000 030/25mhz 16mb fast)

I'm trying to find out whether I'm going to run into performance issues when accessing the drive, or whether it will share similar performance to my current 4GB HD.

[thomas]

Well, the internal IDE bus runs at something around 2 MB per second. Every existing IDE harddrive outruns this easily. So yes, the new HDD will probably run at the same speed as the old one.

On the other hand, at this speed you need ca. 34 minutes to fill the 4GB drive entirely. For a 128 GB drive at the same speed you would need about 18 hours...

[johnim]

its best to use a pc usb to ide adapter or in a pc to copy faster