PCMark 8 Real-World Software Performance
This is our first set of tests with real software traces, which will show us the small differences between SSDs in the wild, outside of contrived benchmarks.
For details on our real-world software performance testing, please click here.
The greatest performance increase you'll see from a single component comes from swapping out mechanical storage in favor of an SSD. As long as your drive of choice is reliable, the difference between one SSD and another is fairly small under normal consumer workloads.
When it comes to SATA-based SSDs, performance differences in a given task might be measured in tenths of a second. Over the course of a long benchmark, those fractions add up. But this metric presents one workload at a time.
This chart combines the results above and an average throughput rating. Suddenly, you see how small deltas turn into more significant aggregate outcomes, even in real-world tasks.
If you have a really heavy workload though, by all means get a high-end unit.
While they're making 3d nand, why don't they add an extra layer for parity and then use the raid-5 algorithm?
e.g. 8 layers for data, adding 1 extra for parity. Not that much extra overhead, but data will be much more reliable.
No you don't. Each sector has CRC right?
So if the sector read fails CRC, simply calculate CRC replacing each layer in turn with the raid parity bit.
All of them will be off except for one with the faulty bit.
And these CRC's can all be calculated in parallel so there would be 0 overhead with regard to time.
In the case of a silent error though, which is what you get if you have an even-count bit error when using parity alone, you have no idea where the error is or even that there ever was an error in the first place. That's why more complex error detection and correction block codes exist and are used wherever read/receive errors carry a high cost, such as performance, reliability, monetary cost or loss of data.
BUT, one significant critique I have was the density limitation. Everything here was based on the ~250 GB drives. Comparing a drive with the exact name, but in a different density, is akin to comparing two entirely different drives.
I realize producing the data can be time consuming, but having the same information at three density points would be extremely helpful for purchasing decisions - lowest, highest, and middle densities.