Re: [newbie] OT 6th question - SCSI vs IDE OT
Adrian, SCSI in itself is not really faster than the latest UDMA ide interfaces. There is another layer of arbitration that has to be gone through to read from a device as the SCSI bus is an idependant bus. I have seen tests some where they took identical drives (except interface) and tested them side by side and the ide drive won because the command has to go through less steps with UDMA than SCSI. So if you get an old SCSI drive don't expect it to be faster than your new 7200 rpm IDE scorcher. Now that i've sort of bashed SCSI I'll give you the advantages. 1. The fastest drives made are SCSI. New harddrive technology debuts in high end SCSI drives. The 15000 rpm Seagate cheatah is one ex. of this. Of course they are some of the most expensive. 2. Much more expandable. You can up to 7 narrow and /or15 wide devices to a single SCSI adaptor card which uses only one irq. This is opposed to 2 devices per channel on IDE at one irq per channel. 3. More variety of devices. DVD, -RAM's,-RW's, tape drives, CD-ROM, RW's, R's, hard drives, solid state storage, scanners, high end printers, and much more. 4. Separate bus. This may be a disadvantage with one device but when it comes to doing high intensity disk activities the scsi buss really shines. It uses a lot less cpu cycles to do inter-bus tranfers (from scsi hdd to cdrw for ex.) That's why scsi cd burners have lower processor utilization than ide ones do. Before burn proof you had a lot less coasters with scsi cdrw's and you do other things while the cdburner was doing it's thing. Caching raid controllers are still almost unheard of in the ide world. In a server enviroment scsi is usually the best way to go. So scsi has a quite a few advantages in the right enviroments. In a typical desktop enviroment it's probably not worth the extra cost. But if you consider yourself a power user and need the expandability and have the cash then go for it. Don S - Original Message - From: "Adrian Smith" [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, October 31, 2000 6:57 PM Subject: [newbie] OT 6th question - SCSI vs IDE OT this came up the other day. someone told me that a SCSI hard drive is faster than an IDE hard drive. i have never used a SCSI drive in my life, so i don't know from experience. is this true?? thanks much no more questions for now Adrian Smith 'de telepone dude Telecom Dept. x 7042 [EMAIL PROTECTED]
Re: [newbie] OT 6th question - SCSI vs IDE OT
In certain situation and with certain applications this is indeed true. However, just as important, if not more so in some instances, is the actual access speed of the HDD in question. If you have a SCSI HDD that spins at 10,000 rpms but only has an access time of 40ms and I have an IDE HDD that spins at 7200 rpms but has an access time of 120ms, I'll take the second HDD every time. Both numbers are important, but to my mind and wallet I tend to look at the access time more than how fast the disk spins. -- Mark Larry is NOT a cucumber...he's a stinkin pickle... WITH WARTS! registered linux user # 182469 =/\= PINE 4.21 =/\= ** Surprisingly on Tue, 31 Oct 2000 Adrian Smith had this to say! this came up the other day. someone told me that a SCSI hard drive is faster than an IDE hard drive. i have never used a SCSI drive in my life, so i don't know from experience. is this true?? thanks much no more questions for now Adrian Smith 'de telepone dude Telecom Dept. x 7042 [EMAIL PROTECTED]
Re: [newbie] OT 6th question - SCSI vs IDE OT
it depends on which kind of SCSI and which kind of IDE. An ATA-100 IDE drive is really fast. Probably quite a bit faster then a narrow SCSI 1 device. Especially if you have a fast CPU. If you have a slower CPU then the SCSI device might be as fast or faster. SCSI works on its own bus that is independent of the CPU while IDE requires that the CPU handle its transactions. This is the primary reason for the speed difference. In many cases the only physical difference between a given IDE and SCSI drive from the same manufacturer is the presence of a SCSI BIOS on one of the otherwise identical drives. ATA-100 devices are very fast. A few days ago at work I was ghosting a hard drive from another hard drive. Both were ATA-100 drives on the asus A7V's promise 100 controller. It was a 900 or so meg transfer and it was completed in under 4 seconds. Fast enough? SCSI is more extensible then IDE though. The only device on a SCSI chain that gets an IRQ is the controller card. Hope that gives you some food for thought! I hate it when I ask a question about hardware and I get "this is better" "no, This is better" with no reasons why ;-) Abe gcobb wrote: SCSI is definitely faster. It's also more costly, but has many benefits. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Adrian Smith Sent: Tuesday, October 31, 2000 6:57 PM To: [EMAIL PROTECTED] Subject: [newbie] OT 6th question - SCSI vs IDE OT this came up the other day. someone told me that a SCSI hard drive is faster than an IDE hard drive. i have never used a SCSI drive in my life, so i don't know from experience. is this true?? thanks much no more questions for now Adrian Smith 'de telepone dude Telecom Dept. x 7042 [EMAIL PROTECTED] -- The frammisgoshes should be distimmed because a frammisgosh is like a farble and distimming is like gosketing and our ancestors always gosketed the farbles. --R.A. Wilson
RE: [newbie] OT 6th question - SCSI vs IDE OT
SCSI is definitely faster. It's also more costly, but has many benefits. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Adrian Smith Sent: Tuesday, October 31, 2000 6:57 PM To: [EMAIL PROTECTED] Subject: [newbie] OT 6th question - SCSI vs IDE OT this came up the other day. someone told me that a SCSI hard drive is faster than an IDE hard drive. i have never used a SCSI drive in my life, so i don't know from experience. is this true?? thanks much no more questions for now Adrian Smith 'de telepone dude Telecom Dept. x 7042 [EMAIL PROTECTED]
