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UBC secondary parameters

2 bytes removed, 13:48, 22 August 2006
formatting fixes
{{UBC toc}}
'''Secondary (dependant) UBC parameters ''' are directly connected
to the [[UBC primary parameters|primary ones]] and can't be configured arbitrarily.
It is important to have a certain safety gap between the <code>barrier</code> and
the <code>limit</code> of the <code>kmemsize</code> parameter
(for example, 10%, as in [[UBC examples]]). Equal <code>barrier</code> and <precode>limit</precode> of
the <code>kmemsize</code> parameter may lead to the situation where the kernel will
need to kill Virtual Environment's applications to keep the <code>kmemsize</code>
socket buffer memory for each socket, as discussed in [[UBC consistency check]]:
<math>tcpsndbuf_{lim} - tcpsndbuf_{bar} \ge 2.5KB \cdot numtcpsock \rm.\cr}</math>
If this restriction is not satisfied, some network connections
socket buffer memory for each socket, as discussed in [[UBC consistency check]]:
<math>tcprcvbuf_{lim} - tcprcvbuf_{bar} \ge 2.5KB \cdot numtcpsock \rm.\cr}</math>
If this restriction is not satisfied, some network connections
in the system plus the <code>kmemsize</code> and other socket buffers is limited
by the hardware resources of the system.
This total limit is discussed in [[UBC systemwide configuration#“Low memory”|“low memory”]].