Using 2280 a Quick scan took about a minute, and a full scan took about 15 minutes. Using 2286 (build 17.1.3394.46) a Quick scan now takes 10 minutes and a full scan 55 minutes. Nothing has changed on my computer except updating Avast. No other virus software has been on my computer. The Quick scan is set to use the Persistent cache, and Full scan is set to Store data in the Persistent cache. The run times given were when no other programs were running. My machine is running Windows 7 SP1.
First did you do a clean install of 2286 or a program update from the avastUI ?
Usually early scans on a new program version take a bit longer (but this seems excessive), I would check your scan settings and ensure that your settings are the same. Some crucial settings for scan speed, I would check to see that it is using the Performance options to use the Persistent cache and to Store data about scans in the Persistent cache. Also look at the ‘Speed up scanning by reading files in the order they are stored on disk.’
Whilst these may help you may need to run a few scans to populate the Persistent cache.
I hope it needs few scans because , as far I’m concerned , the 2nd scan after unabled Persistant cache was as long as the 1st and 3 times longer than with the old version of avast.
More , program update was done from the UI , which obviously did not prevent erasing the memory of previous scans :-\
Don’t forget that new technologies are added to avast.
This means it scans in more ways than the old(er) version, so it is only normal that a scan will take more time.
I did try uninstalling Avast (safe mode, avastclear.exe), and then reinstalling using offline installer but same results.
One thing I noticed and hopefully someone from Avast can respond to, under Quick scan it says “system drive” and under Full scan it says “All hard drives”. Does this mean that Quick scan is now scanning all of the C: whereas it used to only scan key places?