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Beware of aggressive APM on Windows 10 Build 1809

Regeneration

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In build 1809 of Windows 10, Microsoft enabled APM (Advanced Power Management) by default for all SATA storage devices via the AHCI driver. For SSDs this is not a big deal, but for HDDs, APM increases latency, reduces performance and possibly lifespan (parking/unparking heads every few seconds isn't healthy).

Windows 10 Build 1809
54516462_2367787123255971_2563309153099448320_o.jpg

Windows 10 Build 1607
55882239_2367787249922625_4161767075817193472_o.jpg

APM can be disabled with 3rd party software like CrystalDiskInfo (must be re-applied on reboot) or AHCI driver through the registry (permanent solution).
 
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In build 1809 of Windows 10, Microsoft enabled APM (Advanced Power Management) by default for all SATA storage devices via the AHCI driver. For SSDs this is not a big deal, but for HDDs, APM increases latency, reduces performance and possibly lifespan (parking/unparking heads every few seconds isn't healthy).

Windows 10 Build 1809
View attachment 119413

Windows 10 Build 1607
View attachment 119414

APM can be disabled with 3rd party software like CrystalDiskInfo (must be re-applied on reboot) or AHCI driver through the registry (permanent solution).
Not sure what effect it has on my system I haven't benched with and without it on (likely not much as it's a 1TB HDD that is 70% full and used as downloads drive so the performance probably isn't great anyway), however after installing Crystaldiskinfo if you go to Function>Advanced Features>AAM/APM Control> and select your HDD from the drop down and click disable APM has disabled mine even upon restart.
 
Hmm, it's still too early for this. Spinners are still king for $/GB. Unless they're banking on most systems having a single SSD and those who still want to use spinners would know about this and circumvent it?
 
goth both my spinners on a docking station,turns them off only after 30 minutes like the station is advertised.seems the update is not affecting my setup.
 
That's... different? I wouldn't expect a docking station (likely connected via USB) to behave the same as drives directly connected to internal SATA ports.
 
Doesn't seem to bother my external Toshiba 3 TB over USB 3.1 Gen1.
 
decided to use rst again the other day so had to swap back to raid drivers. Seems i forgot how i used to set it up though so had to move to priomocache instead. and set up one of my SSD's as a dedicated lvl 2 storage device.. really cant say i see any difference between primocache and how rst used to work but it is what it is..
Any way none of that matters the point is I think im safe from this bug if im using raid drivers.
 
How do you know this is down to Win10 1809 and not something unrelated?
 
Wouldn't the hard disk drive controller be in control of APM but the ACHI driver now exposes it to Windows 1809?
 
Force APM flag was added to that build for most common SATA controllers. On Intel, APM is now enabled with or without RST.
 
In build 1809 of Windows 10, Microsoft enabled APM (Advanced Power Management) by default for all SATA storage devices via the AHCI driver. For SSDs this is not a big deal, but for HDDs, APM increases latency, reduces performance and possibly lifespan (parking/unparking heads every few seconds isn't healthy).

Windows 10 Build 1809
View attachment 119413

Windows 10 Build 1607
View attachment 119414

APM can be disabled with 3rd party software like CrystalDiskInfo (must be re-applied on reboot) or AHCI driver through the registry (permanent solution).
Could explain why I've been suffering hdd issues ty.
 
On Intel, APM is now enabled with or without RST.

Auto APM on post 12.9.x RSTe drivers has been a PITA.

however after installing Crystaldiskinfo if you go to Function>Advanced Features>AAM/APM Control> and select your HDD from the drop down and click disable APM has disabled mine even upon restart.

APM setting is retained on restart, but check full power off. Even setting HDD firmware to off may be overriden by 1809/RSTe. The best bet is to change APM 80h->C0h to stop excessive head parking while retaining some low power modes.
 
APM can be disabled with 3rd party software like CrystalDiskInfo (must be re-applied on reboot) or AHCI driver through the registry (permanent solution).
What is the registry setting?
 
Clean install of 1809 like two weeks ago. I have not dabbled in the registry at all. I'm not seeing any problems here:
Exos12TB.png


The HD Tune (non-Pro) apparently only detects 2.2 TB of capacity versus 12 TB. Probably why it doesn't curve down like one would expect it to.
 
Low quality post by MrGenius
Why is this my bullshitometer pegged on 100%? Meh...probably that lack of supporting evidence. :nutkick:
 
Sounds like gotta check it after each upgrade.

Never had that problem in Windows 7.
 
I went ahead and found the registry keys, and did the rest of the research.

First, there's no such thing as an "Advanced Power Management" setting(s) in Windows 10.

Second, it's called AHCI Link Power Management, and is set to OFF or "Neither HIPM or DIPM allowed. Link power management is not used" by default. But can be PERMANENTLY enabled/disabled in advanced power options(if added to the GUI).

Third, what you're doing with CrystalDiskInfo is temporarily enabling/disabling/modifying the DIPM(Device-Initiated Power Management) mode. Which is not enabled by default. But can be enabled on its own, or in combination with HIPM(through the registry or advanced power management if added to the GUI).

Fourth, you can set the disk idle timeout to 0(or Never, which is exactly the same thing) in advanced power options(or in the registry), and the hdd/ssd will never power down or park when idle, overriding any of the other power management schemes(as far as powering down, or parking, your hdd/ssd...ever).

Link Power Management mode registry key, aliases and visibility settings
Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Power\PowerSettings\0012ee47-9041-4b5d-9b77-535fba8b1442\0b2d69d7-a2a1-449c-9680-f91c70521c60
https://docs.microsoft.com/en-us/wi...ttings-link-power-management-mode---hipm-dipm

Disk idle timeout registry key, aliases and visibility settings
Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Power\PowerSettings\0012ee47-9041-4b5d-9b77-535fba8b1442\6738e2c4-e8a5-4a42-b16a-e040e769756e
https://docs.microsoft.com/en-us/wi...ower-settings/disk-settings-disk-idle-timeout

How to add or remove AHCI Link Power Management from Power Options
https://www.tenforums.com/tutorials/72971-add-ahci-link-power-management-power-options-windows.html

Lastly, this is seriously much ado about nothing. As it is nothing new with Windows 10(1809 or other). And has not changed in any way since Windows 7.
 
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APM is a head parking technology built on the drive itself (separated from AHCI PM and Windows' power profile). Not all mechanical drives support it. Configured similarly like AAM.

Build 1809 forces APM on the OS drive if supported. Mechanical or not.
 
I went ahead and found the registry keys, and did the rest of the research.

I'm afraid, not. It's nothing to do with link state control of the host AHCI controller. It was first exposed as an issue with 13.x RST AHCI drivers & is a known issue. This is usually noticed as a regular clicking sound and sluggish performance as heads are continually being parked on the landing zone. Effectively it causes the drives that are affected to behave like WD Green EARS series drives. Constantly parking their heads, unnecessarily chewing up load cycles that may reduce the HDD's lifespan. I've disabled APM on my 2x2TB Hitachi via the IBM/Hitachi util, but installing RST 13.x+ turns APM back on & sets to 80h. This happens on every boot & needs to be soft reset by eg Crystaldiskinfo every startup. The default MS SATA AHCI driver didn't do this unitl the latest 1809 patch. @Regeneration now informs us that the default MS AHCI driver is setting APM=80h (I'm guessing) on the OS volume.

No issues here.

Why would this affect some but not others?

Checked your load/unload cycle count? Is it higher than your POH? Does Crystaldiskinfo show APM as a drive feature? What's the value?

To answer your question, depends on whether the APM flag is set in HDD FW. It doesn't matter what value is set. On Win/RST 13.x+ AHCI init, for APM=>APM=80h. Depending on brand/model/series/fw, FW strat may then continually park heads on the landing zone racking up load cycles that can exceed max load cycle count in a short time. Enterprise drives tend not to do this. I have another 2TB Seagate (GrenadaBP) that is affected (APM can't be disabled except via a 3rd party util), while two other 4TB aren't affected. All my spinners are storage only drives. With Linux it's a simple command line fix.
 
Well i got it fixed permanently , Because the issue is that whatever tool i tested it only worked for the Actuall windows session. After reboot it was gone , APM for the Harddisk itself was allways on even after disabling it , it was instant enabled again. On the Old build from my screenshots i didn`t need to do anything of that stuff. It worked out of the Box like it should. And hipm-dipm was disabled @ latest build.
But everytime you add an HDD you should look @ Registry that it is disabled for your new drive . You can disable or enable it for each drive by Hand.

Well to point one, that was the key to Success :

 
Why is this my bullshitometer pegged on 100%? Meh...probably that lack of supporting evidence. :nutkick:

Meh, do want you want. Or install any app and confirm (I confirmed with HDD sentinel it sets apm to 128 not just every boot but regularly).

Second, it's called AHCI Link Power Management

No it's not. You are up an entirely different tree here.

And my long term service branch keeps on giving..

Will effect 1809 LTSC as well.
 
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Some SSDs support APM and may be effected.

I wonder if someone can provide benchmarks with an SSD.
 
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