ACPT-1584

Adding documentation in README.md files that explain the new options in deployment configuration

Author: JacobBrownAustin

app/code/Magento/ApplicationPerformanceMonitor/Profiler/Output/LoggerOutput.php

@@ -67,7 +67,7 @@ public function doOutput(array $metrics, array $information)
         }
         $message = \rtrim($message, ",\n");
         $message .= sprintf("\n}\n");
-        $this->logger->error($message); #################  #######
+        $this->logger->debug($message);
     }
 
     /**

app/code/Magento/ApplicationPerformanceMonitor/README.md

@@ -1,3 +1,64 @@
 **ApplicationPerformanceMonitor**
 
 Monitors the Performance of the Application
+
+To configure, edit app/etc/env.php
+Add these lines.
+
+```
+'application' => [
+    'performance_monitor' => [
+        'logger_output_enable' => 1,
+        'logger_output_verbose' => 0,
+    ]
+]
+```
+
+Use 0 or 1 as the value to enable or disable.
+Both `logger_output_enable` and `logger_output_verbose` default to 0.
+
+The option `logger_output_enable` enables outputting performance metrics to the logger using `debug` method of logger.
+The option `logger_output_verbose` adds additional metrics.
+
+Example output in log file without verbose:
+```
+[2023-10-04T20:48:23.727037+00:00] report.ERROR: "Profile information": {
+        "applicationClass":     "Magento\ApplicationServer\App\Application\Interceptor",
+        "applicationServer":    "1",
+        "threadPreviousRequestCount":   "73",
+        "memoryUsageAfter":     "240 MB",
+        "memoryUsageAfterComparedToPrevious":   "0 B",
+        "memoryUsageDelta":     "118 KB",
+        "peakMemoryUsageAfter": "243 MB",
+        "peakMemoryUsageDelta": "0 B",
+        "wallTimeElapsed":      "0 s"
+}
+```
+
+Example output in log file with verbose:
+```
+[2023-10-04T20:55:31.174304+00:00] report.ERROR: "Profile information": {
+        "applicationClass":     "Magento\ApplicationServer\App\Application\Interceptor",
+        "applicationServer":    "1",
+        "threadPreviousRequestCount":   "42",
+        "memoryUsageBefore":    "239568640 B",
+        "memoryUsageAfter":     "239686808 B",
+        "memoryUsageAfterComparedToPrevious":   "0 B",
+        "memoryUsageDelta":     "118168 B",
+        "peakMemoryUsageBefore":        "243053632 B",
+        "peakMemoryUsageAfter": "243053632 B",
+        "peakMemoryUsageDelta": "0 B",
+        "wallTimeBefore":       "2023-10-04T20:55:31.170300",
+        "wallTimeAfter":        "2023-10-04T20:55:31.174200",
+        "wallTimeElapsed":      "0.0038700103759766 s",
+        "userTimeBefore":       "3.771626 s",
+        "userTimeAfter":        "3.771626 s",
+        "userTimeElapsed":      "0 s",
+        "systemTimeBefore":     "0.095585 s",
+        "systemTimeAfter":      "0.099126 s",
+        "systemTimeElapsed":    "0.003541 s"
+}
+```
+
+The additional options `newrelic_output_enable` and `newrelic_output_verbose` are only used if ApplicationPerformanceMonitorNewRelic module is also installed and enabled.
+See README.md in ApplicationPerformanceMonitorNewRelic for more details on that.

app/code/Magento/ApplicationPerformanceMonitorNewRelic/README.md

@@ -1,3 +1,25 @@
 **ApplicationPerformanceMonitorNewRelic**
 
 Monitors the Performance of the Application in New Relic
+
+To use this module, it requires a New Relic account and the environment already by configured to use that account.
+For general New Relic PHP configuration information, see https://docs.newrelic.com/docs/apm/agents/php-agent/configuration/php-agent-configuration/ .
+
+To configure this module, edit app/etc/env.php
+Add these lines.
+
+```
+'application' => [
+    'performance_monitor' => [
+        'newrelic_output_enable' => 1,
+        'newrelic_output_verbose' => 0,
+    ]
+]
+```
+Use 0 or 1 as the value to enable or disable.
+`newrelic_output_enable` defaults to 1, and `newrelic_output_verbose` defaults to 0.
+
+The option `newrelic_output_enable` enables outputting performance metrics to New Relic.
+The option `newrelic_output_verbose` adds additional metrics
+
+See README.md in ApplicationPerformanceMonitor for details about what metrics are in each.