system
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Is there any way to eliminate or mitigate the file I/O impact of the Avast products? I mean beyond folder exclusions and disabling the File shield.
We have a number of machines deployed where a procedure is performed repeatedly. Without antivirus installed this process takes about 12 minutes. With antivirus, this process takes 18+ minutes. This reduces our output per machine from 40 per shift to 26 per shift. This slowdown occurs even with all realtime shields turned off. The process performed writes a large number of files (~2200) and without antivirus as they are created in the program they appear on disc but with any antivirus the disc output falls further and further behind the program’s output.
Any ideas, suggestions, or products that may work for our situation would be wonderful.
system
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Adding this specific program output directory to a global exclusion doesn’t help?
system
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Not particularly, it reduces it by maybe 1 minute but there is still a significant difference between the performance in this case and without antivirus installed.
I’m not clear why but I think antivirus must have to check files even just to determine that it’s in an excluded directory. What really surprised me was that even disabling all shields didn’t eliminate the slowdown.
We figured it up to somewhere around 150ms per file write delay which would probably insignificant except that it adds up so
system
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Sounds like the path through the disk subsystem is altered when the AV software is installed on the system. The only thing that changes is the action the AV software takes, not to alter the links in the chain, when the real time shield is disabled. Used to see that with filter drivers for AV products, but didn’t realize that still happens with the API’s that Microsoft provides these days.
You didn’t mention - what OS and is it a network location or a local disk?
Have you tried MSE to see if the same performance impact occurs with any AV package registered to the API?
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Sorry, meant to mention that. The machines we’re running currently are Windows XP. If it’s possible that Windows 7 provides better hooks for this we may need to test it (porting our application to Windows 7 is on the roadmap anyway) but I’m not very familiar with the Windows APIs.
Yeah, MSE had the same impact. Avast has actually had the smallest impact with Symantec products having the worst (avast puts us at around 18 minutes symantec at around 25).
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I’m not sure… A developer will have to answer the question about the filter driver and/or mini-filter driver used when avast is installed on XP vs 7…
side note: You’ve got a few short months to get off XP… 