You find that you are having slow performance opening large databases in Lotus Notes.
You find that you are having slower than usual completion times to open large databases (i.e. 1 GB or more).
These symptoms will only occur when accessing the database using bookmark icons (i.e. mail icon) or database links. However, this problem does not occur when accessing databases using the File --> Open --> Lotus Notes Applications menu.
Opening databases using File --> Open --> Lotus Notes Application is a physical data reference. Accessing databases using bookmark icon or database links is a logical data reference, and requires a search method on the Domino server to find the matching database replica.
This problem was not caused by the Lotus Notes or Domino applications. The cause of the problem the usage of NIC card "TCP Offloading" on Windows 2005 (or later) Virtual Server.
This problem is reported by Microsoft in the following KB article:
Windows Virtual Server 2005 (or later)
Diagnosing the problem
The best way to diagnose any connectivity issue is to use Wireshark. Wireshark traces and DEBUG_TCP_ALL debug showed significant packet loss.
Another method to confirm if this is the problem you are experiencing is to compare the times to open a database using a bookmark or database link versus opening the database using File --> Open --> Lotus Notes Application
Resolving the problem
To resolve the issue, please refer to the following Microsoft article which provides workarounds for this issue: