fix(system_monitor): high-memory process are not provided in MEM orde…

…r (backport autowarefoundation#4654) (#769)

fix(system_monitor): high-memory process are not provided in MEM order (autowarefoundation#4654)

* fix(process_monitor): high-memory process are not being provided in %MEM order



* changed option from 'g' to 'n'



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Signed-off-by: ito-san <fumihito.ito@tier4.jp>
Co-authored-by: ito-san <57388357+ito-san@users.noreply.github.com>

system/system_monitor/src/process_monitor/process_monitor.cpp

@@ -401,7 +401,7 @@ void ProcessMonitor::getHighMemoryProcesses(const std::string & output)
     bp::pipe err_pipe{err_fd[0], err_fd[1]};
     bp::ipstream is_err{std::move(err_pipe)};
 
-    bp::child c("sort -r -k 10", bp::std_out > p2, bp::std_err > is_err, bp::std_in < p1);
+    bp::child c("sort -r -k 10 -n", bp::std_out > p2, bp::std_err > is_err, bp::std_in < p1);
     c.wait();
     if (c.exit_code() != 0) {
       is_err >> os.rdbuf();