We all know that full scan can take several hours, especially if there are tons of programs and \ or games installed (even though files larger than 40 mb are, by default, skiped) and we should re-scan the system every week or 2 or so.
So, I would like to suggest the following:
What if scanner could remember clean files and skip them uncless they’re modified (can be done via checksum)
That could slow down initial scan but should speed up later scans.
Hi Maniak. I understand faster scans can be a real benefit. The real time scanner has Stateful setting to stop recently scanned files being scanned again between DB updates, but I guess the logic behind Manual and Schedule not doing this is that for security you would need to scan every file again because the database version would have been updated since the last full scan. Kind regards.
The cache approach for already scanned files is implemented in avast.
From avast help file:
Use transient caching - if transient caching is used, a file that has been scanned, and in which no infection was detected, will not be scanned again the next time it is accessed. However, this is only valid until the next virus definitions update, as the file may contain an infection that was not previously detected but which may be detected based on the new virus definitions. Also, information that the file is clean will only be stored in the computer’s operating (temporary) memory. This means that when the system is restarted the information will be lost, therefore the file will also be scanned again the next time it is accessed after a system restart. This box is checked by default; if you want files to be scanned every time they are accessed, this box should be unchecked.
Use persistent caching - if persistent caching is used and a file is verified as clean, this information will be stored in the permanent memory. This means it will not be lost after a system restart and it is also not affected by virus definition updates. Verified clean files are files which are guaranteed not to contain any virus infection e.g. some operating system files, files signed by trusted publishers, or other files covered by the avast! whitelist. This box is checked by default; if you want all files to be scanned regardless of their trust status, this box should be unchecked.
one way now to implement faster scanning would be to avoid scanning files that are listed in the trusted files list. I don’t know the impact it would have but it should help a little.
one way now to implement faster scanning would be to avoid scanning files that are listed in the trusted files list. I don't know the impact it would have but it should help a little.
Some of Windows system files are now also being added to Trusted Files because the Hash look up is much faster than checking the digital signatures according to egemen:
Let’s add all hash codes of Windows system files to the Trusted Files and let the AV scanner first check hash codes against the Trusted Files before starting the actual scan. May be that would speed things up.