Several Server Questions

[ccd1]

Well, I'm making my own server, but I have a few questions about it all.

1. SCSI vs. IDE: I've heard that the drives themselves are the same, and that the only difference is the controller. What exactly does this controller do that's so special? Will I need a hard drive cooler for RPM's of 10000?

2. RAID: I know that RAID 0 makes a few disks into one big disk, and that RAID 1 mirrors them, but what exactly does RAID 5 do? I've looked it up and it seems rather confusing.

3. Pentium vs Xeon: The prices are pretty much the same for these (Xeon a few dollars more expensive). What does Xeon offer that Pentium can't do and vice-versa?

Thanks.

[AWS]

1) SCSI doesn't use up any of the processor when doing reads and writes as IDE does. The controller has onboard processor, most are risc based, and memory which handles the reads and writes. The bigger the cache the better the performance.

2) Raid 5 you can have a large array of disks and have redundancy as well as a large stripe. You can hotswap drives if one dies and not lose any data. It is the best for webserving.

3) Both will perform great in a server. For a database intense server Xeon is the way to go because you can turn on hyperthreading and it greatly enhances performance. Hyperthreading makes 2 processors look 4 to the OS.

[ccd1]

Originally posted by AWS

2) Raid 5 you can have a large array of disks and have redundancy as well as a large stripe. You can hotswap drives if one dies and not lose any data. It is the best for webserving.


How exactly does this work?

Where is the information mirrored/striped and in what fashion?

[ccd1]

Found this:


RAID-5 volumes provide fault tolerance at a cost of only one additional disk for the volume. This means that if you use three 10-GB disks to create a RAID-5 volume, the volume will have a 20-GB capacity. The remaining 10-GB is used for parity.


I don't understand how 20 GB's of backup can be stored on one 10 GB disk?

[Dave#]

Originally posted by baragon0
Found this:



I don't understand how 20 GB's of backup can be stored on one 10 GB disk?

no 30 gig actual capacity will have 20 in raid.

[ccd1]

Originally posted by Dave#
no 30 gig actual capacity will have 20 in raid.

That's what I meant. If one hard drive were to die, where can that data be replaced? There is only 10 GB of backup data, but 20 GB to back up (because there are 2 10 GB drives).

[eva2000]

Originally posted by baragon0
How exactly does this work?

Where is the information mirrored/striped and in what fashion? search on google for raid 5 and you should get heaps of articles ;)

[ccd1]

Naturally my frist choice before asking here, but it's too complicated.

Well, I got this, but I don't quite know how to interpret it:

http://www.acnc.com/img/raid/05.gif

[eva2000]

full explanation at http://www.arstechnica.com/paedia/r/raid-2.html

[ccd1]

Originally posted by eva2000
full explanation at http://www.arstechnica.com/paedia/r/raid-2.html

Sometimes I wonder what I would do without you.

[eva2000]

Originally posted by baragon0
Sometimes I wonder what I would do without you. i had that bookmarked anyway :)

[ccd1]

On to more fun:

Originally posted by AWS
3) Both will perform great in a server. For a database intense server Xeon is the way to go because you can turn on hyperthreading and it greatly enhances performance. Hyperthreading makes 2 processors look 4 to the OS.

If this is the case, why not always get Xeon processors? They cost the same, how does a Pentium outpreform a Xeon in other things?

[eva2000]

Originally posted by baragon0
On to more fun:



If this is the case, why not always get Xeon processors? They cost the same, how does a Pentium outpreform a Xeon in other things? check out the price of a dual Xeon motherboard and compare that to a dual P3 motherboard ;)

[ccd1]

Originally posted by eva2000
check out the price of a dual Xeon motherboard and compare that to a dual P3 motherboard ;)

Well, all the Xeon motherboards cost more because they all typically add SCSI and RAID. Perhaps this is it?