+| Find critical load using PLRsearch
+| | [Documentation]
+| | ... | Find boundaries for troughput (of given target loss ratio)
+| | ... | using PLRsearch algorithm.
+| | ... | Display results as formatted test message.
+| | ... | Fail if computed lower bound is below minimal rate.
+| | ... | Input rates are understood as uni-directional,
+| | ... | reported result contains bi-directional rates.
+| | ... | TODO: Any additional measurements for debug purposes?
+| | ...
+| | ... | *Arguments:*
+| | ... | - frame_size - L2 Frame Size [B] or IMIX string. Type: int or str
+| | ... | - topology_type - Topology type. Type: string
+| | ... | - minimum_transmit_rate - Lower limit of search [pps]. Type: float
+| | ... | - maximum_transmit_rate - Upper limit of search [pps]. Type: float
+| | ... | - packet_loss_ratio - Accepted loss during search. Type: float
+| | ... | - timeout - Stop when search duration is longer [s]. Type: float
+| | ...
+| | ... | *Example:*
+| | ...
+| | ... | \| Find critical load usingPLR search \| \${64} \| \
+| | ... | 3-node-IPv4 \| \${100000} \| \${14880952} \| \${1e-7} \| \${1800} \
+| | ...
+| | [Arguments] | ${frame_size} | ${topology_type} | ${minimum_transmit_rate}
+| | ... | ${maximum_transmit_rate} | ${packet_loss_ratio}=${1e-7}
+| | ... | ${timeout}=${1800.0}
+| | ...
+| | ${min_rate} = | Set Variable | ${minimum_transmit_rate*2}
+| | ${average} | ${stdev} = | Perform soak search | ${frame_size}
+| | ... | ${topology_type} | ${min_rate} | ${maximum_transmit_rate*2}
+| | ... | ${packet_loss_ratio} | timeout=${timeout}
+| | ${lower} | ${upper} = | Display result of soak search
+| | ... | ${average} | ${stdev} | ${frame_size}
+| | Should Not Be True | ${lower} < ${min_rate}
+| | ... | Lower bound ${lower} is below bidirectional minimum ${min_rate}.
+