How does a diffrent 4KB Random Read/Write speed affect the performance of a SSD when I am comparing similar drives?

Question

If the former drive has 22k IOPS VS below 85k IOPS, how does this matter and what does this mean?

For example, drive 1 and drive 2

Solution

IOPS, or Input/Output Operations Per Second, is probably the most important metric when comparing disks. Basically, it tells you the maximum speed at which that disk can retrieve small, randomly positioned data chunks (4kB).

This is the worst case scenario for any disk (but much worse for a hard disk), because there needs to be a lookup of some kind between every operation. For hard disks, this also means that the head needs to be repositioned between each operation, which slows down transfer tremendously.

On the other hand, if you're upgrading from a HDD, then it doesn't actually even matter that much. For example, a pretty fast 10,000 RPM HDD can give only up to ~150 IOPS. The "slower" disk of the two you posted is capable of getting around 22,000 IOPS. So, you can see that even the slower disk shows great improvement in random access reads.

Other metric like sequential speeds are less relevant for daily work. You can only see true benefits of the advertized peak sequential speeds when copying large files from one folder to another.

Comments

[ganesh]

Five minutes of research would have answered this question. It is not that much effort. Start by looking up what <b>I</b>n/<b>O</b>ut <b>o</b>perations per <b>s</b>econd is. Then read a reviews or two on sites such as Toms Hardware, Anandtech, Tweakers, ... (insert a long list here).

[Mikko Rantalainen]

See also: superuser.com/a/1247862/100154