Follow these instructions to configure memory overload
protection from the administrative console.
About this task
To protect against memory overload, the memory overload protection must initially discover
the maximum rate, that is, calls per second, that can be sustained without exceeding the maximum
percentage of the maximum heap size. As it is discovering the maximum rate, memory overload
protection slowly allows more traffic through without affinity, but will reject the remainder.
Initially, a potentially large number of HTTP requests or SIP messages without affinity will be
rejected with a 503 (unless the error code is changed).
智慧型管理 persists the maximum rate across server restarts, so
it must discover the maximum rate once. The maximum rate can change over time due to changes in the
session or dialog lifetimes, but these lifetimes generally change relatively slowly and memory
overload protection is able to react to such changes. When discovering the maximum rate,
智慧型管理 must keep the rate relatively steady for at least an
averaging window. The averaging window must be at least as long as the lifetime of most of the HTTP
sessions, SIP dialogs, or application sessions. Therefore, the longer the averaging window, the
longer it will take to start.
Memory overload protection is disabled by default.
Memory overload protection is enabled when the memory overload protection (MOP) value is set to less
than 100.
避免困難: To ensure that the memory overload protection is
configured properly, the
-agentlib parameter needs to be set in the
Generic JVM arguments field. Specifying the
-agentlib
parameter is only required in WebSphere® Application
Server Version 8.5.5.2 and earlier. For a version of WebSphere Application Server after version 8.5.5.2, the
-agentlib parameter
is always loaded and does not need to be set, even if the autonomic request flow manager (ARFM) is
disabled.
gotcha
To enable, follow these steps from the administrative
console: