Windows 11 only has 45% of random write speed in Nvme SSD

Question

As you see above, the other performance is about the same, but in RND 4K Q32 T16 the speed has dropped significantly. I know that because the two software versions are different and the condition of the computer is different, it is normal for the performance to fluctuate, but this performance also dropped too much, and the performance remained stable low after many tests at different times.

Answer 1

What I've found with my new Samsung 990 Pro (which is the system boot drive):

• the speeds (especially 4k random write q32t16) are faster in safe mode (~6000 MB/s vs 4600MB/s)
• the "Intel Computing Improvement Program" that comes with "Intel Driver & Support Assistant" causes the 4k random write to drop to around 2500MB/s

Answer 2

That limit of 2500MB/s doesn't seem right; see my previous reply as I measured 5185MB/s. Notice that YMMV with diverse SSD benchmarking tools, I would always trust a first-party tool like Magician's.

Answer 3

i eventualy found that you need to keep yr nvme drive under 25% full or less to keep the read and especially write speeds at maximum with a addlink s70 1tb.

ive since upgraded my system to a x570 msi mpg gaming motherboard and a kc3000 2tb nvme, and im getting 7300ish read and 6950ish writes, so im in a happy place.

i know i should have gone am5, but i only just bought a 5950x cpu and 3080ti last year and got the gen 4 board used for only £75. i dont want to spend a grand on a am5 system until maybe 8950x or 9950x comes out lol

the only fly in my ointment is that the x570 alc realtek sound driver wont show up in win 11 or win 10 even with a new install and with or without msi/realtek website drivers, so ive bought a creative sb used sound card off fleabay for £7 😁😁 fingers crossed when i get it, my 5.1 surround sound will work again

Answer 4

While I believe Windows11 issues involving NVMe random IO write performance are largely resolved, it's important to note that very similar performance anomalies can be created by having a misaligned partition (e.g. partition logical sector start offset to physical flash page alignment). Such misalignment can occur when using cloning software to clone the boot drive partition map and system partition, or if resizing or moving partitions. One might assume these products (one of which ships with a major storage provider's product) would check that partitions are aligned correctly, but they don't. The results are particularly noticeable with random IO write (and related iops) performance, profoundly degrading performance by more than 90%. I'm leaving this response to help those who may happen upon this thread and assume they're dealing with a Windows (or hardware) issue, when in reality the problem is fairly simple to correct.

To find help on correcting a misaligned partition, simply search on "fix partition ssd alignment" and you should find several guides to using 3rd party tools to check and correct partition alignment. A simple check to verify if your partition is improperly aligned is to obtain the partition offset value (System information -> Components -> Storage -> Disks -> Partition Starting Offset) for the partition in question and then divide that value by 4,096 (4k page size); if the resulting value is a whole number, your partition is aligned, otherwise you'll need to align it to correct performance issues.