HP SuperStack 3 Load Balancer Appliance Supported Algorithms Description Round Robin, Response

70CHAPTER 8: CONFIGURING FOR LOAD BALANCING

6Choose a balancing algorithm. The default balance profile is Round-robin. Table 11 describes the available algorithms.

Table 11 Supported Algorithms and Descriptions

Supported Algorithms	Description
Round Robin	Each new connection is assigned to the next server in
	the list. This distributes connections evenly between
	the servers.
Weighted Round Robin	Similar to Round Robin, except that N consecutive new
	connections are assigned to a server before selecting
	the next server in the list, where N is the weight
	assigned to the server. Servers with higher
	performance or capacity should be assigned higher
	weight.
	The weight assigned to the server is assigned using the
	Assign server to service (Advanced)... window. A
	weight field is provided.
Least Connections	Each new connection is assigned to the server having
	the fewest number of open connections. If several
	servers have the same low number of open
	connections, then the new connection is sent to the
	server that was least recently sent a new connection
Weighted Least	Similar to Least Connections, except that N consecutive
Connections	new connections are assigned to a server before next
	selecting the server with the least number of open
	connections, where N is the weight assigned to the
	server
Quickest Last Response	When a new connection is established between a
	client and server, the Server Load Balancer monitors
	the client's first request for data. When the server
	responds to the initial request, the Server Load
	Balancer notes the time delay between the request and
	the response and stores that value as the server's
	response time. Each new connection is sent to the
	server having the fastest response time.
	Since server response time changes dynamically, a
	decay algorithm is applied periodically to all response
	times to prevent a server from being locked out after
	one long response delay
Quickest Average	Similar to Quickest Last Response, except the response
Response	time is averaged over approximately the last eight
	measurements for the server. A decay algorithm is also
	applied to the average response times