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bardin
20-08-2004, 11:39 AM
Hi all,

If I had 2 CD ROM drives and 2 HDDs, I would put one of each type of device on each IDE channel, with the page file on the non-system partition, hoping that it would increase performance.

However I have read several things about maximising I/O performance when using multiple IDE devices:

Put the swap file on a non-system partition. Question: isn't this completely academic unless the partition is on a different drive, AND on a different I/O channel?

Also, according to Mike Minasi's 'Mastering Windows Server 2003', Server 2003 is the first MS OS that can juggle two or more EIDE drives. He says that the driver for EIDE drives, atapi.sys, previously couldn’t juggle two or more EIDE drives. If you told it to simultaneously work with two or more EIDE drives it would just alternate between them.

Now apparently with 2003 EIDE drives can run simultaneously, so long as they are on different EIDE channels.

Can someone shed some light on this, because it makes me wonder whether everything written on the topic until Server 2003 came out has been academic?

Scott Mueller's Upgrading and Repairing PCs seems to agree because he mentions that the main advantage of SCSI drives is that the bus can multitask (or whatever it's called technically!); the drives themselves are identical to the IDE versions.

Another issue, apparently IDE channels like to have the same device type, e.g. Mode 1,2,3,4, UDMA 33,66,100,133, on the channel...so isn't putting a Mode4 CD-ROm drive on the same IDE channel as a UDAM 133 HD not a good idea?

Just trying to make sense of the issue(s), your help appreciated as always!

Cheers,

Brendan

mikebartnz
20-08-2004, 11:55 AM
>Question: isn't this completely academic unless the partition is on a different drive, AND on a different I/O channel?
True in a way but it can still stop a lot of file defragmentation.
>so isn't putting a Mode4 CD-ROm drive on the same IDE channel as a UDAM 133 HD not a good idea?
True again.

tweak\'e
20-08-2004, 06:56 PM
>isn't putting a Mode4 CD-ROm drive on the same IDE channel as a UDAM 133 HD not a good idea?

putting ide hardrive and cdrom on the same ide channel is not really a good idea but normally it will work fine. however you can get problems with some systems usually causeing the harddrive to run at cdrom speed. even when it works perfectly you will get a slow down whenever you are trying to use both drives at once. the pc only accesses one at a time so it copyies data from cd drive, stores it in ram then transfers back to the hardrive. basicly taking 2 steps instead of the usual 1 step. this is slow and can be problematic with cd burners.

> If you told it to simultaneously work with two or more EIDE drives it would just alternate between them.

i really havn't noticed a problem with windows accessing 2 ar more drives at the same time provided they are on seperate ide channels.
when they are on the same ide channel then only one gets accessed at a time. more to do with IDE specs rather than MS drivers (afaik). SCSI dosn't have this problem.