should hard-drives be sharing DMA?

[Pyramix]

 

[Woody419]

Please explain.

 

[bacillus]

I suspect you want to know if you should enable dma for both your hdds in device manager!
yes, you should!

 

[Pyramix]

woody419, i have two hard-drives and windows 98se

when the computer boots up, it shows the dma that each hard-drive is using. turns out both are using udma channel 5. is that alright? or should i somehow be assigning different udma channels to them?

bacillus, enabling dma is not even an option in the device manager (maybe because i have 98). but it seems the dma for both the hard-drives is enabled. the only problem is that they are using the same dma. i was just wondering if that leads to a decrease in performance.

 

[Maggotry]

If I'm understanding you correctly, you're talking about the udma mode. Mode 5 = ATA100, mode 4 =ATA66, etc. It has nothing to do with sharing resources, like an IRQ.

 

[DHL]

<< you're talking about the udma mode. Mode 5 = ATA100, mode 4 =ATA66, etc. It has nothing to do with sharing resources, like an IRQ. >>



I partially agree with this statement, I think you are talking about mode 5 instead of channel 5, as via 686B has 2 bus master IDE controllers, and "bus master" means the IDE controller is equipped with its own DMA hardware, so it should not use the slave DMA resources on the motherboard, which is also known as DMA0-7

However, I think for most common modern southbridges, each IDE controller have only got 1 set of DMA and IRQ hardware, which means if two devices are using the same channel as master and slave, they do share the DMA, IRQ, and the available bandwidth. If the master and slave both try to use the IDE channel, the slave will back off for the master. So there is a possibility that the two drives are sharing resources without knowing ur drive config

If I am spreading false info, please let me know.

Now for my question Pyramix, how do u know both ur drive are DMA enabled even the DMA option is device manager is not available?

 

[PHiuR]

how do u know both ur drive are DMA enabled even the DMA option is device manager is not available?[/i] >>






I have the same question....