This is consistent with the effect of AV software, it is almost a verbatim from the article I referenced:
"When you enable SmartScan, the first user may not see a slowdown, but the second user or every user thereafter may experience a delay of one second or more for each table to open."
>the performance only has started getting bad when more than one XP workstation is accessing the shared data.
Jim Saunders
Microsoft
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