Raid 0 Performance

Quote:

---

Originally Posted by Zak33

so does raid lengthen life then or not?

---

No. There is no mechanism for it to.

Quote:

---

Originally Posted by Zak33

so does raid lengthen life then or not?

---

When the devices contain the same number of NAND chips but with different sizes, then I fail to see how it does not increase the life. You are spreading writes over more NAND chips, which means less writes per chip, which means longer lifetime.

Quote:

---

Originally Posted by shaithis

When the devices contain the same number of NAND chips but with different sizes, then I fail to see how it does not increase the life. You are spreading writes over more NAND chips, which means less writes per chip, which means longer lifetime.

---

But you might as well say that a 240GB SSD lasts longer than a 120GB SSD. It's not the RAID that's making the difference.

Quote:

---

Originally Posted by shaithis

When the devices contain the same number of NAND chips but with different sizes, then I fail to see how it does not increase the life. You are spreading writes over more NAND chips, which means less writes per chip, which means longer lifetime.

---

As already mentioned, the number of chips is not important. The lifetime limitation (for writes) on SSDs is limited by the number of NAND cells available. Larger chips have more cells, therefore have a longer lifetime. Furthermore, by not duplicating the number of non-NAND components, a single bigger drive will be more reliable than having two smaller drives in RAID-0, because RAID-0 has no redundancy so you are doubling your chance of failure.

Quote:

---

Originally Posted by snootyjim

But you might as well say that a 240GB SSD lasts longer than a 120GB SSD. It's not the RAID that's making the difference.

---

Exactly - a 240GB SSD *does* last longer than a 120GB SSD. If you're choice is between a single 240GB SSD and a pair of 120GBs in RAID-0, the single drive will potentially last longer due to the increase reliability.

Quote:

---

Originally Posted by shaithis

When the devices contain the same number of NAND chips but with different sizes, then I fail to see how it does not increase the life. You are spreading writes over more NAND chips, which means less writes per chip, which means longer lifetime.

---

Re-read my post too, the dies used on the drives will be the same size, the number of physical packages isn't really relevant. The whole chip/die doesn't take a hit when you write something to it, only the page/cell, or if data needs to be erased first, the block size which is 256xblock size for 25nm IIRC but that should be somewhat irrelevant with TRIM, some free space and a decent controller. However, if this data is spread across two drives so two controllers, especially for smaller writes, you're potentially modifying a page/block on BOTH drives, which is the point I was trying to make about write amplification.

From the stats that Anandtech published some time back it seems that the current generation of drives will last some years before they wear out with even heavy home use. If that is the case then the drive will be retired because you have outgrown it long before the flash degrades.