Explorer is very slow after connecting external HDD

Question

Recently I've got a new laptop with SSD drive. However, sometimes when I'm connecting external HDD to this laptop, explorer seems to work painfully slow, even when browsing folders on my internal SSD. Indexing on external HDD is turned off. Problem does not exist when I'll restart my computer with external HDD plugged in.

Do you have any ideas what might be causing the problem?

Solution

You have several issues.

1.) the csrss.exe usage is caused by a bug starting with the Update KB2850851. This updates the Win32k.sys driver and this driver causes a high CPU usage while detecting a monitor and the rotation state:

MS is currently investigating this issue. If this is urgent for you, phone the support and remove the Update as a workaround.

2.) the system/kernel usage is caused by the APCI.sys driver which often happens when the CPU overheats (because of the other issue).

3.) the svchost.exe usage comes from Avast (aswSnx.sys):

Comments

[magicandre1981]

do you have a high CPU usage of Explorer or a different process?

[Adam W]

Same Explorer not, but System is consuming ~25% CPU. Also csrss.exe is using 30% (I'm using Polish Win 8 and I'm not sure how this process is called in English, maybe Client Server Run-time Process)! CPU usage is around 90% and this way too much I guess.

[magicandre1981]

follow this: pastebin.com/pgE11HRD and provide a xperf tarce which captures 60s of the high CPU usage.

[Adam W]

Is this the only way to check what is wrong? This file is huge and I will be able to download it earliest by tomorrow. However, I've checked process explorer and I've noticed two things: underneath system process most usage is caused by ntoskrnl.exe and acpi.sys.

[magicandre1981]

yes, xperf is the only way. only select the WPT, which is only 200MB. You don't need the other things.

[Adam W]

Here's the file: dropbox.com/s/7vqq2mti5pwuz1t/cputest.rar hope it doesn't contain any personal data

[magicandre1981]

the trace is too short. And don't use the ugly WPRUI, run the command I posted and capture 60s of the high CPU usage.

[Adam W]

I can't do it again through the command prompt - I did it in the morning for the test and now it says that this file already exists and it can't create new one.

[magicandre1981]

this happens when you run a tool which also uses ETW like ProcessExplorer, Taskmgr, ResMon

[Adam W]

Here's the new file from command promt: dropbox.com/s/sauzxhmcsw7xipd/HighCPUUsage.rar

[Adam W]

That's just... insane! Thank you very much. I must say that I wouldn't even suppose that system update could be causing the problem. It's not a big deal for me, so I'll wait until MS will fix it. How can I check later if they resolved that issue? In terms of point 2 issue, it must be related to the 1st one. So when CPU usage is constantly over 90%, it could be overheating. However, I totally don't know what to do with 3rd issue.

[magicandre1981]

they fixed it when the cpu usage of csrss.exe goes down again. To 3.) The DPS is a diag service of Windows. Avast sends data to it (I have no idea which data).

[Adam W]

So I should simply delete KB2850851?

[magicandre1981]

remove it from Control panel->install updates. Also remove update KB2862768 which also install a newer version of win32k.sys

[Adam W]

I did it. Now System process is 'only' consuming 40-60% of CPU Power. However, Explorer now is not laggy.

[magicandre1981]

ok so your now have the ACPI issue. Is the CPU still overheating? Run CoreTemp (alcpu.com/CoreTemp) and look at the temperature.

[Adam W]

Here are the temperatures: i.imgur.com/IqtmF21.png For me, it does not look as the CPU is overheating. Btw, I've run another xperf, so if that would be helpful I could upload it.

[magicandre1981]

yes upload the trace. Also check if there is a BIOS update

[Adam W]

There is no BIOS update, I've got the latest version about week ago from Samsung SW Update. Extra hint: I realized that discussed problem happens after working only on battery. Grab the new file here: dropbox.com/s/sauzxhmcsw7xipd/HighCPUUsage.rar

[magicandre1981]

you still have the Power Management ACPI.sys/HAL.dll issue. And you still use the same BIOS (P04ABI.013.130220.dg) like in the old trace.

[Adam W]

So what should I do now?

[magicandre1981]

load the default BIOS settings, install Speedfan and increase the cpu cooler fan speed and hope that the temperature decreases and fixes the issue.

[Adam W]

Ok, I'll try and see if it changes something. Do you have any idea why so far it happens only after using laptop on a battery?

[magicandre1981]

try the tool NoteBook FanControl (NBFC): computerbase.de/forum/showthread.php?t=1070494

[Adam W]

To be honest, this program seems to complicated for me. I must create own config file and this is not an easy process. I still don't know why system usage is dramatically increasing while connecting external HDD. Temperatures are jumping up to 60-65*C while I'll do it. It's weird. I mean, plugging in external HDD doesn't require system to do lot of heavy stuff, does it?

[magicandre1981]

ask in the German forum (you can ask in English) if other users have a config for your device.

[Adam W]

Ok, I'll ask them for help. Aha, I've got another clue - when this problem is happening, I can hear that fan inside the laptop is immediately starting to work faster.

[Adam W]

I'm wondering - so when my laptop is overheating, it should still be overheating when I'll restart my computer, shouldn't it? I mean, the boot time (10-15 sec) is not long enough to cool down whole computer. And when this problem occurs and I will immediately restart computer with external HDD already connected, the problem is gone.

[magicandre1981]

look at the temperature before and after the reboot. Is there a large difference?

[Adam W]

No, the temperatures are very similar, almost the same. However, I've got another hint mentioned by someone on closed Facebook group created by Samsung 550P5C owners. He is saying that he has this problem too, but he noticed that it always happend when connecting pendrive / HDD to the USB 3.0 port. After working two hours on battery, I plugged in power and then pendrive to the USB 2.0 and... CPU usage was normal! After that I plugged in pendrive to the USB 3.0 and CPU usage went high! So there is something wrong with USB 3.0 ports.

[magicandre1981]

ok, I have no idea if something is wrong with your USb 3.0 ports. Phone the Samsung support.

[Adam W]

Thank you for your help. It was invaluable! I'll contact Samsung support and see what they can help me with.