I'm planning on connecting 4 old hard drives in a raid 0 configuration. Is that possible with 4 different hard drives in different sizes?

And will I loose space and performance doing that?

Any help would be appreciated

Generally RAID requires matched drives......

The total array size would be equal to the smallest hard drive, and the total array speed would be equal to the slowest hard drive. The extra space I think would be lost.

This is not a good idea for RAID. Do like the professionals suggest and make all your drives the same (down to the model number is preferred).

Thanks for the help!

RAID0 with 4 Drives: wouldn't this give you (approx) an array of 4x the smallest drive and 4x the slowest access - since the read/writes would be simultaneously to the 4 "matched for size" drives??

RAID0 with 4 Drives: wouldn't this give you (approx) an array of 4x the smallest drive and 4x the slowest access??Yes and No. The size is right, but technically the speed isn't.

The relative speed (or lack thereof) on a RAID array isn't cumulative. Since the drives all get read/written at the same time, the speed of the entire array is at least as slow as the slowest drive.

Let's say you have 4 hard drives with random access times of 9ms, 9ms, 10ms, and a whopping 13ms. Ignoring all other latencies and such and assuming we're reading from the array (takes less time than writing) and assuming the starting byte on each drive is on the exact opposite side of the platter from where the read/write heads are (lots of assuming but bear with me) then...

We can say that the time taken to access the first few KB of data is 13ms. If all the drives were the same at 9ms, then that's how long it would take to access the array. 9ms is 44% faster than 13ms!! :eek: And for an array with a slow hard drive, that extra 44% each time would just keep adding up because the faster drives can't deliver their next chunk of data until the slowest drive finishes, even if they're ready.

Now take into account that a hard drive is an entire system unto itself, so if the access time is slow then the rest of the drive is likely slow, too. Everything from the areal density to the buffer size to the spindle speed, slower hard drives are generally slower accross the board. When you put together a RAID array, you don't want any drive to be slower.

It's not like a relay race where a slow team member only affects their leg of the journey - in an array, they're all in it together! No one finishes until the slow one does, and that can lead to poor results.

It's not like a relay race
Agreed. :D More like a three-legged race (or with 4 individuals - a five-legged race) with the group only going as fast as the slowest member. He He - and the analogy can be extended to the size of the disk being the length of that individual's racing lane. The other runners have to stop when one gets to the end of it's own lane.

Admittedly having four (or whatever) matched individuals able to race in sync is best - but it must be possible for 3 matched with one slowbie to transfer more data in the same time as the 3 matched ones on their own. Actually "having the race" would be the only way to measure this! ;)