Avast has slowed Time Machine to a very slow crawl

[VelcroJP]

I have been running Time Machine since I purchased my iMac in 2013.  I installed Avast (free edition) following a very good review in the New York Times.  While I am very happy with Avast itself, it has slowed down opening of files in Word and Excel (in particular), especially when the documents are password protected.  It has also slowed Time Machine backups to an intolerable crawl -- backups (hourly) took less than a minute before installing Avast, now take three or four minutes, during which almost nothing else will work.  I have disabled automatic backups, which kind of defeats the purpose of Time Machine.  How can I resolve the problem?

[ondrej.kolacek]

Hello,

we are not aware of any slowdowns regarding Time Machine backups. What is your setup? Where is the backup located? On an external harddrive? Could you please check Activity monitor for suspicious conditions? Do the relevant Avast processes (com.avast.fileshield and com.avast.daemon) consume a lot of CPU during backup? What is the memory pressure like in Memory tab during that time? Which version of Mac OS do you use?

I will ask testers to check out the performance of TM once again, but knowing more would increase chance of us reproducing a potential issue.

Kind regards,
Ondrej Kolacek

[.: Mac :.]

VelcroJP,

Is this by change backing up to a time capsule or other form of NAS? Or Rather to a locally attached drive?

[VelcroJP]

iMac running "High Sierra" 10.13.6 with 4TB Seagate external disk, attached via USB3.  Backup was even slower on 1TB "G Drive" (also USB3).
Temporarily doing manual backups when iMac not too busy!
My previous reply seems to have been "lost".
Activity monitor shows nothing out of the ordinary (CPU, Memory, network etc.) but, like going to the dentist with pain -- pain goes as soon as you reach dentist's office!
Will "play around" with turning off internet connection and turning off file scanning while doing backups.
I have an "offline backup-of-last-resort"which takes some time to do and I have been putting off updating it (It doesn't use Time Machine) and had hoped to resolve issue before doing so.

[ondrej.kolacek]

Hello,

we have done some stress testing and while the impact has been nowhere near yours, we will try to find a way to lessen the impact, hopefully in the next version of Avast. We also have few ideas planned which could lessen the scan impact in some cases; but these will take some time to implement

Thank you a lot for reporting this; I will try to remember to post here if we find a way around the slowdown.

Kind regards,
Ondrej Kolacek

[VelcroJP]

Thank you.