CAV very heavy on system while scanning

I am currently using Comodo Firewall with D+ and NOD32 antivirus. This combination has worked well for me for nearly a year, but I am keen to switch to Comodo Firewall with D+ and also the AV component.

NOD32 has always been a very light AV, and CAV also seems to do well. The biggest difference I find is while doing a system scan with CAV, everything I try to do is significantly slowed down. Even opening “My Computer” takes about 10 seconds! Opening Microsoft Word (which normally only takes half a second), takes at least 10-15 seconds. By the way, I have 2Gb of RAM on XP Pro, and I have a Core 2 duo processor (so it’s not poor hardware). Yes I am really picky about this, so apologies in advance.

I would really like to switch to the full CIS (including the AV component) very soon, but the above is stopping me at present. Does anyone have similar experiences regarding a sluggish system while CAV is scanning?

With regards to poor detection rates, I don’t think this is a big issue, given the amazing D+. I also use Superantispyware as an on-demand scanner, so that pretty much covers everything.


Do you have any other Security Software installed? A 15 second slow down is something new to me, considering CIS is one of the lightest security suites (if not the lightest) out there.

Have you ever done a defrag, registry clean up, etc?


yes! I hear you, scanning with CIS destroys my system! there are similar threads about this on the forum, but I think that this is some kind of serious bug that has not been taken in to account.

Good to know I am not alone in this. I tried CIS with the Antivirus component again and noticed once more the significant slowdowns in my system while the AV is scanning. Comodo really needs to optimise and improve this aspect of the AV, IMHO.

Sticking with NOD32 for now, which is a great AV too (but not free).

Good luck.

EDIT: 3xist, my computer is very well defragged and optimised I assure you. I may have exaggerated on the 15 second load time though. I agree CIS is probably the lightest security software out there, but it is NOT light “while the AV is doing an on-demand full system scan”. That’s the key point right there.

There are two incompatible things here. Speed of scan and system load. It would be nice to have an option to scan with less system load.

Well, not really…

It’s not that way on every system. On my system, I notice no slowdowns whatsoever.

That’s the fun part about writing software. There are countless different system configurations with different software installed. It’s impossible to predict how your software will behave on every system. The best that you can do is hope that your users will give you enough detailed feedback that you can hopefully pin down problems they may be experiencing…

I used NOD32 Security Suite and I’m now using CIS. On my system, Comodo takes up 1/5th of the memory Nod32 used just sitting in the taskbar. When it’s scanning, Comodo still uses around 1/2 the memory NOD32 used just sitting in the taskbar.

When the scan is running I notice a short delay opening My Computer (1-2 second delay max). The rest of the folders open like normal. Programs open slower, but of course… this assumes your running a scan and using the computer at the same time (not the smartest thing to do to begin with)

I think a previous suggestion to use a buffer when scanning would improve performance and eliminate any slowdown you are perceiving.