Better Hard Drives?

Posted on: September 30th, 2009

Hard drive is one of the top two components in a computer that tends to fail before anything else. The other one is the power supply.

While a power supply fix is fairly easy and inexpensive, a hard drive issue is a lot more complicated. First problem is that it holds all your data! People understandably want to get their data recovered. And that sometimes is a slow and expensive process if at all possible.

Why are hard drive so failure prone?

Well, because it’s one of the few components in the computer which contains moving parts. And moving parts mean friction and deterioration. And because of the demand for higher and higher capacity drives they have to contain small parts with very high precision movements. If something gets misaligned, even a tiny bit, then you get a non-working hard drive on your hands. And they are not serviceable because of the high precision internal assembly.

What’s in the future?

You are probably quite familiar with the little flash drive that you use to store your data on, or to transfer files between computers. These are based on special type of memory chips that don’t lose their content once the power source is gone (non-volatile). They went through quite a bit of development in the last couple of years. They become smaller, faster and more reliable.

These memory chips are the basis of the new breed of hard drives, the Solid State Drives – or SSD’s. They offer several adventages:

- No moving parts. The whole thing is based on electronic circuits. This means no mechanical degradation and much higher resistance to mechanical shock (eg drops or jolts).
- Smaller weight. No magnets, no metal disks and no metal casing needed.
- Lower power consumption. No spinning disk, no moving head.
- No noise due to no moving parts.
- Faster operation, especially reading from the disk. Virtually no seek time (the time it takes to move the read/write head from one position to another. Because there isn’t any read/write head therefore it doesn’t matter which part of the disk is accessed the access time will be the same). Reading is also several times faster than from a conventional hard disk. There are reports of boot up times with SSDs as low as few seconds (using Vista).

Just as with everything that good there are some kickbacks:

- Price: SSD’s are still several times more expensive than the conventional hard drive of the same capacity. But prices are coming down quickly and capacity is increasing a lot faster than the conventional hard drives did. For example there are already SSD with the capacity of 500Gb. The spinning disk technology needed several decades to reach that figure, SSDs needed only a couple of years.
- Slow Write: The memory chips used in the SSD’s need more time to write something than to read it. It makes sense since it needs to be “burned” in to make it last. This is actually not a big issue. The write speed is already near, or above the conventional hard drives and it will just increase in the future.
- Gradual degradation: With each write cycle there will be some degradation due to the “burning” process necessary to make the data stored to last beyond the first power down. This has also pretty much worked out. A simple solution is used where each block has a counter or write cycles and if that reaches the unsafe level then it’s simply reallocated somewhere else. The SSD’s already reached a longer life expectancy than the spinning disks. Because the degradation is quite predictable the hard drive can notify the computer about the coming failure well in advance so actions can be taken to prevent data loss. That is much, much better than the current hard drives that can crash from one moment to another.

Summary

SSDs are definitely the way of the future. They already made their way into the higher end laptop machines. As the prices fall and the capacities climb they will make it to the everyday computers. I very much look forward to their arrival. I hate messing with failed hard drives.

In actual fact there are some model now that are in the affordable price range. For example I just saw a 32GB SSD (laptop size) for $85 (for this price you can get a 500GB conventional hard drive ) which is big enough to have Windows and some basic programs on it. The largest SSD I saw is a 512Gb one for $1,500 (ouch!). But the prices are way better than they were a year ago!