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<chapter Id="runtime">

<title>Operating System Environment</title>

On Linux 2.6 and later, an additional measure is to modify the

kernel's behavior so that it will not <quote>overcommit</> memory.

Although this setting will not prevent the OOM killer from

invoking altogether, it will lower the chances significantly and

being invoked altogether, it will lower the chances significantly and

will therefore lead to more robust system behavior. (It might also

cause fork() to fail when the machine appears to have available memory

because of other applications with careless memory allocation.) This

cause <function>fork()</> to fail when the machine appears to have

available memory but it is actually reserved

to other applications with careless memory allocation.) This

is done by selecting strict overcommit mode via

<command>sysctl</command>:

<programlisting>