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So basically in class (during a database course) we had to install and run CrystalDiskMark and analyse the numbers.
The only thing I couldn't quite grasp is the fact that my computer (using an SSD) had a higher mb/s number at queue depth 32 then it had with queue depth 1.
If I'm not mistaken queue depth is the amount of tasks waiting to be processed where 1 is typically for a normal user while 32 is more towards a server.
At 4Kb queue depth 1 it had 31,74 mb/s read and 24,13 mb/s write. At 4Kb queue depth 32 it had 163,6 mb/s read and 60,68 mb/s write.
For reading that's more then 5x and more then double the writing. Why does it have that much more mb/s at 32 queue depth? I thought it would be higher at 1 queue depth
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I think your source link has died, unfortunately. Here's a different mirror:
http://www.samsung.com/global/business/semiconductor/minisite/SSD/M2M/html/whitepaper/whitepaper08.html
I think another relevant counterpoint to Samsung's source is that the "preference" is only one-way, from all the SSDs I've seen. You get either strong QD32 / weak QD1 or strong QD32 / strong QD1.
I've never seen weak QD32 / strong QD1. And I mean "strong" relative to other drives, not within the same drive (where QD32 will always be faster than QD1).