how often avast update service checks if there’s any updates available? and am i able to get automatic updates if i set update service (aswUpdSv.exe) to ‘manual’?
Hi Avaster and Welcome to the Forums
I found this in the Avast Help File it is a wealth of Knowledge hope this helps
Automatic. This choice ensures that your database or program will be as up-to-date as possible. Every time you connect to the Internet, avast! checks whether your virus database or program is older than the one available on our server. If they are different, it downloads the data currently missing on your computer.
Ask when update is available. The principle is the same as in the previous case, but the update will not be started automatically; you will only be notified that a newer version is available, and it will be up to you to download it either immediately, or later. This is the default setting.
Manual. The update will not be automated in any way and you will always have to run it manually.
Update now. When you click this text, the update of the database or program will be started immediately.
VPS updates usually number about 3-4 a week although there is no set schedule, there have been times during high virus activity when I have seen 4 in a day.
avast checks frequently (if an internet connection already exists) for updates and if an update is available you will get it. Updates are incremental (you don’t have to download large files), so the file sizes are small and it completes quickly so it shouldn’t interfere greatly with your browsing, etc.
Leave the services as they are, there is an interface to change update settings, right click the avast icon, Program Settings, Update (Basic).
Welcome to the forums.
avast checks if there is an available connection each 40 seconds.
If there isn’t, wait more 40 seconds to check. Checking does not take more than one second and, of course, does not use the Internet band.
If there is a connection, check for an update. If there is not any new file to download, wait 4 hours to start checking again. If there is an available update, start it and install it. Again, wait 4 hours to check the next time.
Some of this settings could be configurated different, I posted the default values of the avast4.ini file.
The updates are incremental. This is the wiser method of updating I have ever seen in a antivirus 
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