Hello,
I noticed that when I start the PC, for many minutes (about 10/15 minutes) the hard disk usage is high, in total it remains at 100% and the app that uses the hard disk the most is Avast antivirus.
It’s normal?
You are not alone seeing that. It has been annoying me for the past few versions of avast free. Clearing all my Browser caches seems to help a little but HDD is still being hammered by Avast for minutes after startup. I don’t know what the hell it is doing with the HDD for so long after startup, maybe it is scanning the whole HDD every time. I have just been putting up with it.
If Avast have an explanation, please share it with us frustrated users.
@ Nunzio77
Your image isn’t showing Avast as the culprit - just that the Disk column is showing a total of 100%, not what is responsible for that. If it is Avast you need to scroll down to show where Avast is using this disk activity.
As in my image listed by name for all Avast processes, this image is for explanation only as it isn’t directly after startup.
I would also suggest adding your system specs in your forum profile > signature.
The characteristics of my PC and operating system are in my signature.
During normal PC operation, after those indicated minutes of PC startup, Avast’s resource situation is similar to yours. I’m talking about the minutes after starting up the PC in which Avast is the process that writes the most to the hard disk as you can see from the image for many minutes. It obviously contributes very actively to the total use of the hard disk. The problem is that it takes many minutes.
Yes, but you don’t show it, so there is no real way to identify why.
This however can be difficult right after startup, but try and get to the desktop task manager and try and capture the actual avast task responsible. If this was when your screenshot was taken you should be able to scroll down (and order by the Name column, grouping all the avast tasks together).
Whilst your system spec is now old, my old Win XP Pro PC desktop had a Core 2 Duo and 4GB ram (this is almost 5 years ago) and I can’t recall such issues. However Avast has moved forward too.
I would also ask if you have a lot of apps/programs set to run on startup ?
If so try limiting those to see there is one causing avast to scan disk activity.
Here are the print screens.
Auto-running apps are only the essential ones.
I think part of the problem here is the values displayed in that column, as it is showing 4,3 MB/s (MegaBytes per second) in your image, which isn’t a value I would associate with Hard Drive activity/usage and how this is converted to arrive at 100% of what. I’m not even sure this figure is accurate, as 100% of what your disk being full or 100% activity.
All I can think of is Avasts Service is accessing 4.3Mbs of data per second, but then every value in that column when added up would have represent the physical limit of data accessed per second. Even in your previous image the Avast Service was only showing 1,6 MB/s and at the same time Disk was showing 100%
Thanks David R. 
A response from the developers would also be appreciated. 8)
You’re welcome.
@DavidR and all, so this is still a sign that Avast slows down during the first few moments of starting up the PC during its use?
From what I see on Task Manager (Win10 22H2) at startup, Disk runs 100% for ten mins or so. When Task Manager is sorted on Disk load, there are different Avast processes showing top or near top contribututors that burden. I have got used to not trying to doing anything constructive on the PC until the disk thrashing eventually calms down. For me this is not new to recent Avast Free versions but has been a pain for some time.
Is this on SSD or on a traditional spinning HDD?
Disk thrashing sounds like the OS and/or Avast and/or other applications want to do a lot of small reads and writes. A HDD can’t deal with that very well, whereas an SSD handles that much better.
I’ve had my OS on SSD since 2009 and can’t imagine going back. This year even my mass storage went SSD. No more HDD in the PC. Faster, quieter, less moving parts.
There will come a time, and we may already be there, where an SSD is expected. The OS and apps will be written with an SSD in mind. This might be what is going on.
HDD
Also HDD
When the resolution?
The problem with making a fix, is they first have to identify the problem. From what has been covered in this topic doesn’t give enough to identify the issue to attempt a fix.
Ordinarily Avast would ask you to Record a performance problem - Avast UI > Settings > General ? Troubleshooting > Record a performance problem - Open Recorder - Start Recording.
I don’t know what happens after this as I have never done this. I guess having given a brief description (here I would give the URL to this topic as further reference) - Start Recording. You would have to restart after that to try and replicate the problem and have the monitoring recorded. After this disk usage activity dies down stop the recording. Presumably this would then need to be submitted to avast for analysis (I don’t know how, never having used this function).
Ok. Thanks!
You’re welcome, hopefully it will help.
When you are actioning this procedure, if you can document what happens at the various stages to fill in the blanks in my procedure above.
Hi,
I expose what I mentioned in the forum in Spanish: Reading the forum in English I notice several issues related to the ram or the slow start of the antivirus interface and that is why my question: Normal behavior of the Antivirus when starting the PC? Is it a change? I noticed about 3 months ago and I thought either it’s an error or it’s to optimize the start, if so it generates 2 problems: low performance when starting and poor performance during use. Why? Windows is terrible managing the cache and Ram , I suppose that users like me with 8Gb of ram or less will notice it more or slow hard drives. By the way, a few weeks ago I installed a laptop with Windows 10 and Avast had the same behavior.
Attached link to better see the start of the PC: https://youtu.be/6ekEaPN3P1s
Greetings and sorry for the English that I use as a translator
Thank you for reporting. Can you please reproduce this issue and provide us the performance recording (at the moment when it is happening). You can either record and submit the recording from UI (Settings > General → Troubleshooting > Record a performance problem) or you can follow the procedure described here:
https://forum.avast.com/index.php?topic=237567.0
in either way please let us then know (here on the forum) that you have finished uploading, so we can have a look and analyze it with priority. Thank you and we are sorry for these inconveniences.