There’s a serious performance bug in the latest avast! version. 
avast! slows down Windows Vista.
avast! causes a lot of hard drive activity every time you launch an application although it’s already cached in RAM, it seems avast to be incompatible with Vista’s Superfetch.
Try to disable avast and your Windows Vista will fly!!!
Please fix this bug. Thanks
Hello,
the lastest avast version is 4.7.1098 and it was released 4th December - so it’s quite long time!
avast detects Superfetch activities and it fully cooperates with Vista - so I believe this slowdown is not caused by avast.
Haven’t you changed the settings or installed any apps lately?
You can download Process Monitor tool (http://technet.microsoft.com/en-us/sysinternals/bb896645.aspx), which shows you what file activities are performed during application startup.
Please let us know what you’ll find out.
Thanks!
PS. how long does it take than you’ll notice that slowdown? immediately or after X hours… ? thanks.
Seriously you can’t notice the difference?
It’s clear that Avast slow downs Vista a lot forcing frequent HD loadings instead of using Superfetch.
Just try a fresh & clean Vista installation and use it WITHOUT Avast, then install it: you’ll notice how slow it becomes on loading/saving apps, browsing dirs, etc. because HD is always at work for all these operations (thing that Superfetch should avoid).
There’s also a thread open on an italian Forum: http://www.hwupgrade.it/forum/showthread.php?p=21488276&posted=1 where many users confirmed this sad (because they all love Avast) experience.
Please investigate and fix this problem: Vista with Avast gets slow making HDs overwork unnecessary.
Is this taking place only on first run of the application, or every run?
Also, does it make any difference if you e.g. pause the avast Standard Shield provider?
Thanks
Vlk
Every run, that’s why you notice it. Yes, you notice the big difference even simply pausing the Standard Shield.
I tried to remove almost any sub-option from Standard Shield to isolate the problem but Vista was still very “HD-crunching” 
Only thing you can do to avoid this problem is A. remove Avast :-[ or B. pause the Standard provider…
Belive me, if you have a Vista machine the test is very simple: disable the Standard provider and you’ll suddenly notice the big difference!
Which application are you testing it with?
And what hardware do use use? (CPU, RAM,…)
Doesn’t matter: any.
Do you think it’s a specific problem on my config? You’re wrong: the problem has been confirmed by many users with very diffrent HW and SW. Trust me.
You can’t notice the difference with or without the Standard provider enabled? It’s evident.
I understand you’ve coded it and so are skeptical because you can’t see nothing strange in the sources but trust me: if you just run Vista without Standard provider enabled you’ll see a big difference in every operation Superfetch does: HD’s led won’t even flash sometimes. With Standard provider enabled instead the HD is heavily affected in all operations.
Man, we’re not a one-man company - we have a plenty of machines here, some of them having Vista of course.
So, it might be wise to answer Vlk’s questions (about the particular configuration) 
INTEL CORE 2 DUO E6600, 3 GB PC800 DDR2, GE-FORCE 8800 GTS 320 MB VRAM, audio card integrated, motherboard ASUS P5K-E DELUXE, HD MAXTOR 320 GB SATA II, windows vista ultimate 32 bit
i have the same problem, with avast all slow (not too slow) all programs.
As I said: it doesn’t matter the HW and SW. If I say I have 2GB, AMD Sempron 3400+ and Vista home basic, but the problem has been confirmed also on a PC 1… Intel G33 Express…Intel® Core™ 2 Duo E6750…Ram ddr2 1x2 samsung 667mhz Vista Home Premium, or a Toshiba Satellite A100-017 Vista Ultimate machine what does this demonstrates? As I said it’s been confirmed by many users with very different HW and SW config. This means it’s not a SW or HW specific config problem but a weird bug somewhere in Avast.
The problem is evident simply disabling or enabling Standard provider.
I’ll reply to all your questions but first tell me: did you test it with a Vista machine and Standard provider ON/OFF? Do you really can’t see the difference a lot of other users see about HD overworking when loading/saving any apps?
When it’s ON it’s like Superfetch datas are ignored…
I noticed that too (avast slowing down vista) but no problem on xp.
That’s why I disabled everything in standard shield exept “analyze created/mofified files” and I let NOD32’s AMON do my “standard shield” as it works perfectly with avast!.
ex : opening MS EXCEL 2007 = 5 sec with standard shield on normal and 2 sec with my perso settings (cf above)
I Think that it’s the DLL scan wich is very slow
my hd load load load… and only when avast is enabled…
Just to add my input. I have been suffering the same since my new laptop was bought with Vista business installed in May 2007.
As an example - with a 9 Megabyte excel file saved on a central MS SBS 2003 server the file load and save performance is markedly different with and without the standard shield enabled. With the shield disabled I can load up the file, press a “refresh button” which activates a macro which pulls down updated information from another server and save the file again - this process takes 30 seconds. With the standard shield enabled, the same process takes 2 minutes and 10 seconds - for a great deal of the time the hard disc activity light is constantly lit. This is not an issue with every other PC on the network which run XP Professional.
With some of the larger files I use it can take up to 5 minutes to save a file across the network. To be honest, this rubbish performance has prevented me ordering any other vista machines for the network. Until I read this forum I had thought it was a vista problem. I have just renewed my site licence for 2 years with Avast.
Richard
Well… maybe it’s time to me to review the guiltiness of Vista in my notebook too.
MS Office is not that fast as it is on XP, for sure…
Yes I confirm I have the same problem he have this is my configuration ASUS A8N SLI DELUXE Athlon64 FX 60 2GB OCZ ddr 400 dual channel @ 200mhz 2,5 2 3 5 GEFORCE 8600 gts hd 2 maxtor dmax 9 80gb raid 0 dvd-r Lg 4167b
without Avast my pc i s more more faster and I’m sorry because I really like Avast.
Sure… I won’t expect that an antivirus has zero impact in the performance.
The question point here if it is acceptable, if there are other solutions to this inconvenience.
Protection takes resources. The equation will be always there. Even comparing products, you’ll need to compare apples with apples and oranges with oranges.
I know! but the difference is awesome like more than 50% slow to open a Oo writer for example and with another antivirus (AVI…) for example I can’t tell the difference but with avast every program I load slow down so much
Try opening the Standard Shield settings and uncheck to scan open/create/modified files and test the impact.
No the fact is that Avast slow-downs a lot Vista forcing HD frequent loadings/writings. It’s not a little (expected by a virus scanner) slow down. With the Standard provider disabled there’s a big difference. It’s an HD unnecessary overwork. Vista has Superfetch that wroks really fine reducing HD access to minimal. With Standard provider ON every action forces some HD noise, which is not normal.
Just test this: disable the Standard provider (=pause) yourself for a short time and you’ll immediately notice the difference in HD loadings. You cannnot deny the difference if you make this simple test.
It looks like Avast routines bypass and don’t cooperate with Vista’s Superfetch.
As I’ve already written I tried to disable any option in Standard provider but was still the same. Only way to stop this strange behaviour was to Pause it or uncheck the whole 1st page settings… It’s like Nortn + Kaspy together on a 486! Ok, maybe not so slow but the difference is evident however…
PS
How do I disable my email address view in this forum? You can see it? I’ve set “Hide from public” but I still see the little mail icon aside…
I’m an user like you. The programmers should say if avast cooperates or not with Superfetch.
I don’t know.
You’re the only that can see your own email, not the other users.