Autodesk 15606-011408-9330 - MAPGUIDE R6.3 SITE LIC-UPG R6 User Manual page 57

Autodesk
MapGuide
Viewer
request layers 1 & 3
request layers 2 & 4
request layers 5 & 6
return data
draw layer 1
draw layers
2, 3, 4, 5, & 6
Simultaneous request model
MapAgents and Server Ranking
When the ISAPI, NSAPI, or CGI MapAgents receive a request from a
MapGuide client, they rank the available servers and select one to which they
dispatch the request. If the chosen server is offline or invalid, the MapAgent
tries the next server in the rank.
CGI MapAgent
Each Autodesk MapGuide client request invokes a separate instance of the
CGI MapAgent that lasts only the duration of the request. Because of this, the
CGI MapAgent cannot track the number of requests dispatched to each
server. It randomly selects an available server for each request and then ranks
all other servers based on their proximity to this server in the list that appears
in the Window's registry. The CGI MapAgent distributes requests evenly
among all available servers regardless of their current workload.
Autodesk
MapGuide
Server A
process
request
return data
Architecture and Performance
Autodesk
MapGuide
Server B
process
request
return data
parallel process
serial process
Autodesk
MapGuide
Server C
process
request
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