Speed Performance tested (Desktop)
1) using Window defender on win 10 Pro 1607
[Boot fr SSD Plextor PX256M5P]-SATA3
1a) custom scan C: (256GB SSD) 30.6GB in 14min => 36.42MB/s
1b) custom scan D: (4TB HUS HDD) 135GB in 53min => 42.45MB/s
SSD boot---can't see what files is being scanned.
2) using Window Security Essentials on win 7 Ultimate
[Boot fr 4TB HDD HUS 7K4000 partition as 2drives]
2a) custom scan C: (4TB HUS HDD) 135GB in 60min => 37.5MB/s
2b) custom scan Q: (256GB SSD) 30.6GB in 14min => 36.42MB/s
HDD boot---can see what the files/directory/etc is being scanned.
SSD spec as Read 5xxMB/s and Write 5xxMB/s
SSD custom scan speed will be similar if use 850Pro 512GB
while HDD spec as 100MB/s -200MB/s or greater for newer HDD
Suspect Bottleneck in hardware bus transfer?
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Agreed boot up is faster using SSD vs HDD.
guessing only, maybe av scans not the entire file but certain parts only (eg starting portion?) - depending on analyst knowing where malware code is commonly found
so if ur hdd is 135gb full, but made of fewer large movie files (example)
vs
ur ssd is 30.6gb full, but made if many many small system files (example)
the av may actually need to do more work scanning & analysing the smaller files in ur ssd...?
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edit:
scratch dat, the limiting rate is probably the av engine's analysis rate
the case where hdd scan rate is higher than ssd scan rate, maybe due to above guessing tat it contains more large movie files (example) tat only got the starting block analyzed & the rest skipped...?