Windows 10 slow disc access (resolved)

Question

I'm a Win 7 user, so Win 10 is all new to me. I've been upgrading a laptop for a friend and they use Windows 10. What I noticed is the HDD access is really slow.

Here are some info: It is a HP Envy 15 with an i7 core. Rather new laptop. It has 16 GB of RAM. 5400 RPM HDD 1TB with 800GB free on ACHI or RAID (default HP setting). It is set to automatically defrag the HDD. It has a 256GB NVMe SSD I recently installed.

Edited Details: Ok had a chance to look at the system.

First the HDD is a Samsung, but the brand is irrelevant because I was able to do a Crystal Mark test.

1. Crystal Mark test showed direct access is 175mb/s, identical to my own Seagate. All the random read etc... were relatively the same. The HDD is working fine, not only so, the Crystal Mark test ran fine on this Win 10. So this makes it all the more puzzling.

2. In the cache program I used, the direct access read on the cache files was also around 150-170mb/s. And with RAM cached reading, it was 800mb/s, roughly 6-8 times faster. In this Win 10 system, I was only getting 30-50mb/s reading and cached at 80-90mb/s, only 2x faster.

In a 3rd older system I used with Win 7, even though the Crystal Mark test showed 60mb/s direct access read, the cache showed 15mb/s, the cache read was 100-150mB/s, essentially 10x faster.

So something is not right with the Win 10.

Second, Win 10 is ver 1903. I don't know why b/c automatic update is on, but that's the version. I read around and there are some people complaining this version slowed down their disc access. However, I'm skeptical b/c they said the same thing about 1907 and again 1909.

The problem is, those people with disc access issues have massive problems such as slow boot up, slow saves, and most importantly, their slow disc access is visible in Crystal Mark. That is not the case in my issue.

According to Crystal Mark, the disc access is fine. However during the cache test, file access is slowed. In the old Win 7 I tested, the problem was the antivirus - Windows Essential Security. In that scenario, problem was resolved after putting the cache program and subsequent disk image in exclusion.

This Win 10 is also running Windows Essential Security, but putting the cache program in exclusion did not resolve the issue. It means something else is accessing these files each time they're read.

I have narrowed it down to these possibilities and hope some people can verify or help me brainstorm:

1. Some Win 10 service or process is still scanning every file accessed. It is not Win's superfetch, prefetch, windows search, as I've already verified this.

2. Some 3rd party software is still interfering with file access, either another antivirus or antimalwarez.

3. It might be Windows 10 RAM compression. However, I find this unlikely as the file access without RAM was already slow.

4. Could actually just be the cache program doesn't work well with Win 10. But I find this unlikely as this is a very simple program and the concept should not have issues between windows. There was no issue installation and setup.

I'm leaning towards 1 & 2, seems like there's some sort of extra security protocol that is simply scanning every file accessed.

----------- EDIT -------------

Solution: Thanks everyone who contributed. This issue is resolved. Actually technically there was no issue, I simply misunderstood how the cache test was done.

Only the 1st 2-4GB of the caching would improve the reading by 8-10x because it stores the most critical slow random 4k reads from softwares on the HDD to the cache. Anything beyond this point the cache is less efficient as the read from HDD/SSD at this point on small program files in sequential read is pretty much the same.

Since the cache I created was 32GB, only the first 2-4GB had the ratio of 8x+, rest is only 2x. The test is randomly choosing data from the cache, hence why most of the data was in the 2x field.

Thanks again everyone.