When Avast update the virus definitions automatically it went from 4,035,193 something and now it 2,968,255 :o this has happen to me 4 times in each day going back and forth. Next day I get 4 million and the next following day I get 2 million virus definitions, what the heck is going on :o :o :o
Edit my last virus definitions update is 121115-1 16/11/2012 at 9:28:37 AM
Interesting, I’ll check it here.
ATM I’m on 2,968,255. Let’s see if it changes to 4,x during the day…
ya, got 2,968,555 here too.
A bit ago (year or more) Avast! did some consolidating of the definitions, and reduced the number from over 3,000,000 to under 2,500,000. Caused a bit of a ruckus then and some thought the a/v protection was lesser, not more.
Point in case: Malwarebytes definitions database sizes increase with time, and suddenly get smaller. Impact of this was that this was caused by definitions for much older spyware/malware, was removed, as they may feel it obsolete and not needed anymore; size of downloaded database fluctuates and thus maybe Avast! is doing the same thing here?
Could be normal housekeeping, is all.
Housekeeping might be involved, still it shouldn’t be an “up/down-situation”, like Speedy reported.
I’m fully aware about the housekeeping of the virus definitions however it was very strange when it happen, so will check in the morning or lunch time when I get online and do a screenshot if it happen again 
PS. I’m not bloody drunk…well I did have a couple of scotch whiskey :
:
Guys it happen again the fifth time just after mid-night tonight at 12:06am through the update and I was about to go to bed see screenshot below. My last virus definitions update is now 121116-0 number of definition is 4,058,528
What the heck is going on :o :o :o :o :o :o :o :o :o :o :o :o :o :o :o
I haven’t a clue what is going on, but then again ‘I never’ check the number of virus definitions as I feel the number is irrelevant. Since I don’t check, I obviously don’t notice the fluctuation or get worried about it.
Well you should worried what happen if the virus definition cut in half again, and how will I know if I’m protected by the numbers of virus definition if a true virus slip through my PC and suddenly Avast forgot to keep the housekeeping up to date.
Edit: Any way I’m going to bed as Avast is given me a bloody headache.
They are just numbers I have always maintained that the number is meaningless, how can you actually count that number when one signature can detect many variants.
For the same sort of reason I don’t look in the avast logs, if there is no errors displayed to the screen I leave them alone.
David R is correct! avast! VPS engine is an automated function that is always combining multiple definitions into a single definition, always automated, always computing, and will never stop. This is how avast! shrinks those updates for more efficiency! And this occurs real-time!
Fluctuation confirmed.
After today’s update it jumped to 4,060,508.
Note: After 3 updates the definitions are only increasing, so this (temporary) glitch has been fixed.