SSD's are NAND based flash memory isn't it ?

which means that they have limited no: of writes ?

so my questions are as follows

1) after completing this limited no: of writes , will an SSD drive become un-usable ?

2) according to the article given here:-

http://www.tomshardware.com/forum/20...-samsung-flash

Flash has a limited no. of writes, usually a maximum of 100,000 operations in the same location.

Does that mean that at the time being, HDD's are a better proposition when compared to SSD's ?

No. Look up wear levelling.


No. What determines which is a better proposition is largely economics. So to determine which is better, you have to look at the economics of the application. If you could say which was a better proposition without considering the application, there would probably only be one on the market.

Intel's MLC SSDs has got a life span of 100GB per day x 5 year

after some researching on the net this is what i have concluded


Pros of SSD:-

1) less power consuming
2) no spin-up time
3) fast random access to data


Cons of SSD:-

1) High cost per G.B
2) lower drive capacity
3) relatively low write speed
4) wear leveling to ensure a single block of flash memory is not used extensively
5) wear leveling can cause problems with data encryption techniques

Well, that's a surpise:

After reading you initial post, I had no idea that this would have been the type of information that you were trying to get. There are a couple of points that are questionable, but, in general, you have the right idea. The cost per gigabyte of capacity is higher, but they have some performance advantages.

I don't directly see wear levelling as a disadvantage; yes, you pay for someone to incorporate wear levelling into their chips, but once it is there, it is there, and you don't, as a user, have to do anything else to make it happen, and it improves the longevity of the device.

And, relatively low write speed? Relative to what? If it is only relative to the read speed of an SSD, then it is not really a disadvantage so much as a lack of an advantage.

Just to quote a rather extreme 'corner case' at you; imagine a case in which there is a database server, which primarily does reads rather than writes on a small-ish data set; it could be the case that in order to get adequate performance with conventional hard drives you would have to add an extra server to get extra spindles...even if that wasn't a problem from cooling/power points of view, it would be clear that adding this extra server would be more expensive than substituting a single small SSD for a hard drive in the critical part of the database.

(There would also be the possibility of using higher performance hard drives, but you'll be surprised how much that these have higher costs per Gb than standard, consumer, drives.)

So, in this, admittedly extreme, case you can argue that the advantage of SSDs is that they are cheaper when looked at from a systems point of view. While this is not the normal case (if it was the normal case, more people would be using SSDs for their home computers), I am pointing this out to ensure that you aware of the dangers of over-generalisation.