JSI Tip 1732. SP6 will fix network performance problems with MSMQ tinygrams.

MSMQ sends small packets, tinygrams, which experience a 300ms delay before being sent.

The Windows NT TCP/IP stack uses the Nagle algorithm, defined in RFC 896, to prevent small packets from flooding the network. The algorithm only allows one un-acknowledged small packet per connection. This conflicts with MSMQ's tinygrams.

When SP6 is released, you can disable the Nagle algorithm for MSMQ by navigating to:

HKEY_LOCAL_MACHINESoftwareMicrosoftMSMQParameters

On the Edit menu, Add Value name TcpNoDelay, as a type REG_SZ. Set the string value to 1. Stop and restart the Microsoft Message Queue Service in Control Panel / Services.

NOTE: No, I don't know when SP6 will be released.