BigMemory 4.4.0 | Product Documentation | BigMemory Max High-Availability Guide | Configuring the HealthChecker Properties | Calculating HealthChecker Maximum
 
Calculating HealthChecker Maximum
The following formula can help you compute the maximum time in milliseconds it will take HealthChecker to discover failed or disconnected remote nodes:
Max Time = (ping.idletime) + socketConnectCount * [(ping.interval * ping.probes)
+ (socketConnectTimeout * ping.interval)]
Note the following about the formula:
*The response time to a socket-connection attempt is less than or equal to (socketConnectTimeout * ping.interval). For calculating the worst-case scenario (absolute maximum time), the equality is used. In most real-world situations the socket-connect response time is likely to be close to 0 and the formula can be simplified to the following:
Max Time = (ping.idletime) + [socketConnectCount * (ping.interval *
ping.probes) + ping.interval]
*ping.idletime, the trigger for the full HealthChecker process, is counted once since it is in effect only once each time the process is triggered.
*socketConnectCount is a multiplier that is in incremented as long as a positive response is received for each socket connection attempt.
*The formula yields an ideal value, since slight variations in actual times can occur.
*To prevent clients from disconnecting too quickly in a situation where an active server is temporarily disconnected from both the backup server and those clients, ensure that the Max Time for L1->L2 is approximately 8-12 seconds longer than for L2->L2. If the values are too close together, then in certain situations the active server may kill the backup and refuse to allow clients to reconnect.