diff --git a/docsys/src/main/resources/logback-docsys.xml b/docsys/src/main/resources/logback-docsys.xml
deleted file mode 100644
index 75ee168cf..000000000
--- a/docsys/src/main/resources/logback-docsys.xml
+++ /dev/null
@@ -1,39 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<configuration>
-    <statusListener class="ch.qos.logback.core.status.NopStatusListener"/>
-
-    <appender name="DOCSLOGS" class="ch.qos.logback.core.rolling.RollingFileAppender">
-        <param name="Append" value="false"/>
-        <append>false</append>
-        <file>logs/docserver.log</file>
-        <encoder>
-            <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-        </encoder>
-        <rollingPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
-            <append>false</append>
-            <fileNamePattern>logs/archived/app.%d{yyyy-MM-dd}.%i.log.gz</fileNamePattern>
-            <!-- each archived file, size max 10MB -->
-            <maxFileSize>50MB</maxFileSize>
-            <!-- total size of all archive files, if total size > 20GB, it will delete old archived file -->
-            <totalSizeCap>250GB</totalSizeCap>
-            <!-- 60 days to keep -->
-            <maxHistory>1</maxHistory>
-            <cleanHistoryOnStart>true</cleanHistoryOnStart>
-        </rollingPolicy>
-    </appender>
-    <logger name="io.nosqlbench.docsys" level="debug" additivity="false">
-        <appender-ref ref="DOCSLOGS"/>
-    </logger>
-
-    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
-        <encoder>
-            <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-        </encoder>
-    </appender>
-
-    <root level="trace">
-        <appender-ref ref="STDOUT"/>
-<!--        <appender-ref ref="DOCSLOGS"/>-->
-    </root>
-
-</configuration>
\ No newline at end of file
diff --git a/engine-api/src/test/resources/log4j-test.xml b/engine-api/src/test/resources/log4j-test.xml
new file mode 100644
index 000000000..70176aaf6
--- /dev/null
+++ b/engine-api/src/test/resources/log4j-test.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration status="debug" strict="true" name="XMLConfigTest"
+               packages="org.apache.logging.log4j.test">
+
+  <Filter type="ThresholdFilter" level="trace"/>
+
+  <Appenders>
+    <Appender type="Console" name="STDOUT">
+      <Layout type="PatternLayout" pattern="%7r %-5level [%t] %-12logger{0} %msg%n%throwable"/>
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="DENY" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="DENY" onMismatch="ACCEPT"/>
+      </Filters>
+    </Appender>
+    <Appender type="Console" name="FLOW">
+      <Layout type="PatternLayout" pattern="%C{1}.%M %m %ex%n"/><!-- class and line number -->
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="ACCEPT" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="ACCEPT" onMismatch="DENY"/>
+      </Filters>
+    </Appender>
+    <Appender type="File" name="APPSLOG" fileName="docs/apps.log">
+      <Layout type="PatternLayout">
+        <Pattern>%d %p %C{1.} [%t] %m%n</Pattern>
+      </Layout>
+    </Appender>
+  </Appenders>
+
+  <Loggers>
+
+    <Logger name="io.nosqlbench.docsys" level="info" additivity="false" specificity="trace">
+      <AppenderRef ref="APPSLOG"/>
+    </Logger>
+
+    <Root level="trace">
+      <AppenderRef ref="STDOUT"/>
+    </Root>
+
+  </Loggers>
+
+</Configuration>
\ No newline at end of file
diff --git a/engine-api/src/test/resources/logback-test.xml b/engine-api/src/test/resources/logback-test.xml
deleted file mode 100644
index b352084ec..000000000
--- a/engine-api/src/test/resources/logback-test.xml
+++ /dev/null
@@ -1,14 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!-- logback-test.xml for engine-api -->
-<configuration debug="true">
-
-  <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
-    <layout class="ch.qos.logback.classic.PatternLayout">
-      <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-    </layout>
-  </appender>
-
-  <root level="debug">
-    <appender-ref ref="STDOUT"/>
-  </root>
-</configuration>
\ No newline at end of file
diff --git a/engine-cli/src/main/resources/log4j.xml b/engine-cli/src/main/resources/log4j.xml
new file mode 100644
index 000000000..70176aaf6
--- /dev/null
+++ b/engine-cli/src/main/resources/log4j.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration status="debug" strict="true" name="XMLConfigTest"
+               packages="org.apache.logging.log4j.test">
+
+  <Filter type="ThresholdFilter" level="trace"/>
+
+  <Appenders>
+    <Appender type="Console" name="STDOUT">
+      <Layout type="PatternLayout" pattern="%7r %-5level [%t] %-12logger{0} %msg%n%throwable"/>
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="DENY" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="DENY" onMismatch="ACCEPT"/>
+      </Filters>
+    </Appender>
+    <Appender type="Console" name="FLOW">
+      <Layout type="PatternLayout" pattern="%C{1}.%M %m %ex%n"/><!-- class and line number -->
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="ACCEPT" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="ACCEPT" onMismatch="DENY"/>
+      </Filters>
+    </Appender>
+    <Appender type="File" name="APPSLOG" fileName="docs/apps.log">
+      <Layout type="PatternLayout">
+        <Pattern>%d %p %C{1.} [%t] %m%n</Pattern>
+      </Layout>
+    </Appender>
+  </Appenders>
+
+  <Loggers>
+
+    <Logger name="io.nosqlbench.docsys" level="info" additivity="false" specificity="trace">
+      <AppenderRef ref="APPSLOG"/>
+    </Logger>
+
+    <Root level="trace">
+      <AppenderRef ref="STDOUT"/>
+    </Root>
+
+  </Loggers>
+
+</Configuration>
\ No newline at end of file
diff --git a/engine-cli/src/main/resources/logback.xml b/engine-cli/src/main/resources/logback.xml
deleted file mode 100644
index 7513a2819..000000000
--- a/engine-cli/src/main/resources/logback.xml
+++ /dev/null
@@ -1,34 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!-- logback.xml for engine-cli -->
-<configuration>
-    <statusListener class="ch.qos.logback.core.status.NopStatusListener" />
-
-    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
-        <encoder>
-            <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-        </encoder>
-    </appender>
-
-    <appender name="DOCSLOGS" class="ch.qos.logback.core.rolling.RollingFileAppender">
-        <file>logs/docserver.log</file>
-        <encoder>
-            <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-        </encoder>
-        <rollingPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
-            <fileNamePattern>logs/archived/app.%d{yyyy-MM-dd}.%i.log.gz</fileNamePattern>
-            <!-- each archived file, size max 10MB -->
-            <maxFileSize>50MB</maxFileSize>
-            <!-- total size of all archive files, if total size > 20GB, it will delete old archived file -->
-            <totalSizeCap>250GB</totalSizeCap>
-            <!-- 60 days to keep -->
-            <maxHistory>1</maxHistory>
-        </rollingPolicy>
-    </appender>
-
-    <logger name="io.nosqlbench.docsys" level="info" additivity="true">
-        <appender-ref ref="DOCSLOGS"/>
-    </logger>
-
-    <!--<logger name="io.nosqlbench" specificity="TRACE"/>-->
-
-</configuration>
\ No newline at end of file
diff --git a/engine-cli/src/test/resources/log4j-test.xml b/engine-cli/src/test/resources/log4j-test.xml
new file mode 100644
index 000000000..70176aaf6
--- /dev/null
+++ b/engine-cli/src/test/resources/log4j-test.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration status="debug" strict="true" name="XMLConfigTest"
+               packages="org.apache.logging.log4j.test">
+
+  <Filter type="ThresholdFilter" level="trace"/>
+
+  <Appenders>
+    <Appender type="Console" name="STDOUT">
+      <Layout type="PatternLayout" pattern="%7r %-5level [%t] %-12logger{0} %msg%n%throwable"/>
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="DENY" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="DENY" onMismatch="ACCEPT"/>
+      </Filters>
+    </Appender>
+    <Appender type="Console" name="FLOW">
+      <Layout type="PatternLayout" pattern="%C{1}.%M %m %ex%n"/><!-- class and line number -->
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="ACCEPT" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="ACCEPT" onMismatch="DENY"/>
+      </Filters>
+    </Appender>
+    <Appender type="File" name="APPSLOG" fileName="docs/apps.log">
+      <Layout type="PatternLayout">
+        <Pattern>%d %p %C{1.} [%t] %m%n</Pattern>
+      </Layout>
+    </Appender>
+  </Appenders>
+
+  <Loggers>
+
+    <Logger name="io.nosqlbench.docsys" level="info" additivity="false" specificity="trace">
+      <AppenderRef ref="APPSLOG"/>
+    </Logger>
+
+    <Root level="trace">
+      <AppenderRef ref="STDOUT"/>
+    </Root>
+
+  </Loggers>
+
+</Configuration>
\ No newline at end of file
diff --git a/engine-cli/src/test/resources/logback-test.xml b/engine-cli/src/test/resources/logback-test.xml
deleted file mode 100644
index b5e147ade..000000000
--- a/engine-cli/src/test/resources/logback-test.xml
+++ /dev/null
@@ -1,15 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-
-<!-- logback-test for nb-test -->
-<configuration>
-
-  <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
-    <layout class="ch.qos.logback.classic.PatternLayout">
-      <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-    </layout>
-  </appender>
-
-  <root level="trace">
-    <appender-ref ref="STDOUT" />
-  </root>
-</configuration>
\ No newline at end of file
diff --git a/engine-core/src/main/resources/log4j.xml b/engine-core/src/main/resources/log4j.xml
new file mode 100644
index 000000000..70176aaf6
--- /dev/null
+++ b/engine-core/src/main/resources/log4j.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration status="debug" strict="true" name="XMLConfigTest"
+               packages="org.apache.logging.log4j.test">
+
+  <Filter type="ThresholdFilter" level="trace"/>
+
+  <Appenders>
+    <Appender type="Console" name="STDOUT">
+      <Layout type="PatternLayout" pattern="%7r %-5level [%t] %-12logger{0} %msg%n%throwable"/>
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="DENY" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="DENY" onMismatch="ACCEPT"/>
+      </Filters>
+    </Appender>
+    <Appender type="Console" name="FLOW">
+      <Layout type="PatternLayout" pattern="%C{1}.%M %m %ex%n"/><!-- class and line number -->
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="ACCEPT" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="ACCEPT" onMismatch="DENY"/>
+      </Filters>
+    </Appender>
+    <Appender type="File" name="APPSLOG" fileName="docs/apps.log">
+      <Layout type="PatternLayout">
+        <Pattern>%d %p %C{1.} [%t] %m%n</Pattern>
+      </Layout>
+    </Appender>
+  </Appenders>
+
+  <Loggers>
+
+    <Logger name="io.nosqlbench.docsys" level="info" additivity="false" specificity="trace">
+      <AppenderRef ref="APPSLOG"/>
+    </Logger>
+
+    <Root level="trace">
+      <AppenderRef ref="STDOUT"/>
+    </Root>
+
+  </Loggers>
+
+</Configuration>
\ No newline at end of file
diff --git a/engine-core/src/main/resources/logback.xml b/engine-core/src/main/resources/logback.xml
deleted file mode 100644
index 12e2f501d..000000000
--- a/engine-core/src/main/resources/logback.xml
+++ /dev/null
@@ -1,14 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!-- logback.xml for engine-core -->
-<configuration>
-<statusListener class="ch.qos.logback.core.status.NopStatusListener" />
-
-<!--<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">-->
-    <!--<encoder>-->
-      <!--<Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>-->
-    <!--</encoder>-->
-  <!--</appender>-->
-
-  <logger name="io.nosqlbench" specificity="TRACE"/>
-
-</configuration>
diff --git a/engine-core/src/test/resources/log4j-test.xml b/engine-core/src/test/resources/log4j-test.xml
new file mode 100644
index 000000000..70176aaf6
--- /dev/null
+++ b/engine-core/src/test/resources/log4j-test.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration status="debug" strict="true" name="XMLConfigTest"
+               packages="org.apache.logging.log4j.test">
+
+  <Filter type="ThresholdFilter" level="trace"/>
+
+  <Appenders>
+    <Appender type="Console" name="STDOUT">
+      <Layout type="PatternLayout" pattern="%7r %-5level [%t] %-12logger{0} %msg%n%throwable"/>
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="DENY" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="DENY" onMismatch="ACCEPT"/>
+      </Filters>
+    </Appender>
+    <Appender type="Console" name="FLOW">
+      <Layout type="PatternLayout" pattern="%C{1}.%M %m %ex%n"/><!-- class and line number -->
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="ACCEPT" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="ACCEPT" onMismatch="DENY"/>
+      </Filters>
+    </Appender>
+    <Appender type="File" name="APPSLOG" fileName="docs/apps.log">
+      <Layout type="PatternLayout">
+        <Pattern>%d %p %C{1.} [%t] %m%n</Pattern>
+      </Layout>
+    </Appender>
+  </Appenders>
+
+  <Loggers>
+
+    <Logger name="io.nosqlbench.docsys" level="info" additivity="false" specificity="trace">
+      <AppenderRef ref="APPSLOG"/>
+    </Logger>
+
+    <Root level="trace">
+      <AppenderRef ref="STDOUT"/>
+    </Root>
+
+  </Loggers>
+
+</Configuration>
\ No newline at end of file
diff --git a/engine-core/src/test/resources/logback-test.xml b/engine-core/src/test/resources/logback-test.xml
deleted file mode 100644
index 5fd8688bc..000000000
--- a/engine-core/src/test/resources/logback-test.xml
+++ /dev/null
@@ -1,16 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!-- logback-test for engine-core -->
-<configuration>
-
-  <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
-    <layout class="ch.qos.logback.classic.PatternLayout">
-      <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-    </layout>
-  </appender>
-
-  <logger name="io.nosqlbench" specificity="INFO"/>
-
-  <root level="debug">
-    <appender-ref ref="STDOUT" />
-  </root>
-</configuration>
\ No newline at end of file
diff --git a/nb/src/main/resources/log4j.xml b/nb/src/main/resources/log4j.xml
new file mode 100644
index 000000000..70176aaf6
--- /dev/null
+++ b/nb/src/main/resources/log4j.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration status="debug" strict="true" name="XMLConfigTest"
+               packages="org.apache.logging.log4j.test">
+
+  <Filter type="ThresholdFilter" level="trace"/>
+
+  <Appenders>
+    <Appender type="Console" name="STDOUT">
+      <Layout type="PatternLayout" pattern="%7r %-5level [%t] %-12logger{0} %msg%n%throwable"/>
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="DENY" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="DENY" onMismatch="ACCEPT"/>
+      </Filters>
+    </Appender>
+    <Appender type="Console" name="FLOW">
+      <Layout type="PatternLayout" pattern="%C{1}.%M %m %ex%n"/><!-- class and line number -->
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="ACCEPT" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="ACCEPT" onMismatch="DENY"/>
+      </Filters>
+    </Appender>
+    <Appender type="File" name="APPSLOG" fileName="docs/apps.log">
+      <Layout type="PatternLayout">
+        <Pattern>%d %p %C{1.} [%t] %m%n</Pattern>
+      </Layout>
+    </Appender>
+  </Appenders>
+
+  <Loggers>
+
+    <Logger name="io.nosqlbench.docsys" level="info" additivity="false" specificity="trace">
+      <AppenderRef ref="APPSLOG"/>
+    </Logger>
+
+    <Root level="trace">
+      <AppenderRef ref="STDOUT"/>
+    </Root>
+
+  </Loggers>
+
+</Configuration>
\ No newline at end of file
diff --git a/nb/src/main/resources/logback.xml b/nb/src/main/resources/logback.xml
deleted file mode 100644
index 4016f4bf8..000000000
--- a/nb/src/main/resources/logback.xml
+++ /dev/null
@@ -1,40 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!-- logback.xml for engine-core -->
-<configuration>
-    <statusListener class="ch.qos.logback.core.status.NopStatusListener"/>
-
-    <!--<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">-->
-    <!--<encoder>-->
-    <!--<Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>-->
-    <!--</encoder>-->
-    <!--</appender>-->
-
-    <logger name="io.nosqlbench" specificity="TRACE"/>
-
-    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
-        <encoder>
-            <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-        </encoder>
-    </appender>
-
-    <appender name="DOCSLOGS" class="ch.qos.logback.core.rolling.RollingFileAppender">
-        <file>logs/docserver.log</file>
-        <encoder>
-            <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-        </encoder>
-        <rollingPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedRollingPolicy">
-            <fileNamePattern>logs/archived/app.%d{yyyy-MM-dd}.%i.log.gz</fileNamePattern>
-            <!-- each archived file, size max 10MB -->
-            <maxFileSize>50MB</maxFileSize>
-            <!-- total size of all archive files, if total size > 20GB, it will delete old archived file -->
-            <totalSizeCap>250GB</totalSizeCap>
-            <!-- 60 days to keep -->
-            <maxHistory>1</maxHistory>
-        </rollingPolicy>
-    </appender>
-
-    <logger name="io.nosqlbench.docsys" level="info" additivity="true">
-        <appender-ref ref="DOCSLOGS"/>
-    </logger>
-
-</configuration>
diff --git a/virtdata-lang/src/test/resources/log4j-test.xml b/virtdata-lang/src/test/resources/log4j-test.xml
new file mode 100644
index 000000000..70176aaf6
--- /dev/null
+++ b/virtdata-lang/src/test/resources/log4j-test.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration status="debug" strict="true" name="XMLConfigTest"
+               packages="org.apache.logging.log4j.test">
+
+  <Filter type="ThresholdFilter" level="trace"/>
+
+  <Appenders>
+    <Appender type="Console" name="STDOUT">
+      <Layout type="PatternLayout" pattern="%7r %-5level [%t] %-12logger{0} %msg%n%throwable"/>
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="DENY" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="DENY" onMismatch="ACCEPT"/>
+      </Filters>
+    </Appender>
+    <Appender type="Console" name="FLOW">
+      <Layout type="PatternLayout" pattern="%C{1}.%M %m %ex%n"/><!-- class and line number -->
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="ACCEPT" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="ACCEPT" onMismatch="DENY"/>
+      </Filters>
+    </Appender>
+    <Appender type="File" name="APPSLOG" fileName="docs/apps.log">
+      <Layout type="PatternLayout">
+        <Pattern>%d %p %C{1.} [%t] %m%n</Pattern>
+      </Layout>
+    </Appender>
+  </Appenders>
+
+  <Loggers>
+
+    <Logger name="io.nosqlbench.docsys" level="info" additivity="false" specificity="trace">
+      <AppenderRef ref="APPSLOG"/>
+    </Logger>
+
+    <Root level="trace">
+      <AppenderRef ref="STDOUT"/>
+    </Root>
+
+  </Loggers>
+
+</Configuration>
\ No newline at end of file
diff --git a/virtdata-lang/src/test/resources/logback-test.xml b/virtdata-lang/src/test/resources/logback-test.xml
deleted file mode 100644
index 5060e6eed..000000000
--- a/virtdata-lang/src/test/resources/logback-test.xml
+++ /dev/null
@@ -1,13 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<configuration>
-
-  <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
-    <layout class="ch.qos.logback.classic.PatternLayout">
-      <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-    </layout>
-  </appender>
-
-  <root level="debug">
-    <appender-ref ref="STDOUT" />
-  </root>
-</configuration>
\ No newline at end of file
diff --git a/virtdata-lib-basics/src/test/resources/log4j-test.xml b/virtdata-lib-basics/src/test/resources/log4j-test.xml
new file mode 100644
index 000000000..70176aaf6
--- /dev/null
+++ b/virtdata-lib-basics/src/test/resources/log4j-test.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration status="debug" strict="true" name="XMLConfigTest"
+               packages="org.apache.logging.log4j.test">
+
+  <Filter type="ThresholdFilter" level="trace"/>
+
+  <Appenders>
+    <Appender type="Console" name="STDOUT">
+      <Layout type="PatternLayout" pattern="%7r %-5level [%t] %-12logger{0} %msg%n%throwable"/>
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="DENY" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="DENY" onMismatch="ACCEPT"/>
+      </Filters>
+    </Appender>
+    <Appender type="Console" name="FLOW">
+      <Layout type="PatternLayout" pattern="%C{1}.%M %m %ex%n"/><!-- class and line number -->
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="ACCEPT" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="ACCEPT" onMismatch="DENY"/>
+      </Filters>
+    </Appender>
+    <Appender type="File" name="APPSLOG" fileName="docs/apps.log">
+      <Layout type="PatternLayout">
+        <Pattern>%d %p %C{1.} [%t] %m%n</Pattern>
+      </Layout>
+    </Appender>
+  </Appenders>
+
+  <Loggers>
+
+    <Logger name="io.nosqlbench.docsys" level="info" additivity="false" specificity="trace">
+      <AppenderRef ref="APPSLOG"/>
+    </Logger>
+
+    <Root level="trace">
+      <AppenderRef ref="STDOUT"/>
+    </Root>
+
+  </Loggers>
+
+</Configuration>
\ No newline at end of file
diff --git a/virtdata-lib-basics/src/test/resources/logback-test.xml b/virtdata-lib-basics/src/test/resources/logback-test.xml
deleted file mode 100644
index c38e933b1..000000000
--- a/virtdata-lib-basics/src/test/resources/logback-test.xml
+++ /dev/null
@@ -1,14 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<configuration>
-
-  <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
-    <layout class="ch.qos.logback.classic.PatternLayout">
-      <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-    </layout>
-  </appender>
-
-  <root level="trace">
-    <appender-ref ref="STDOUT" />
-  </root>
-
-</configuration>
\ No newline at end of file
diff --git a/virtdata-userlibs/src/main/resources/log4j.xml b/virtdata-userlibs/src/main/resources/log4j.xml
new file mode 100644
index 000000000..70176aaf6
--- /dev/null
+++ b/virtdata-userlibs/src/main/resources/log4j.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration status="debug" strict="true" name="XMLConfigTest"
+               packages="org.apache.logging.log4j.test">
+
+  <Filter type="ThresholdFilter" level="trace"/>
+
+  <Appenders>
+    <Appender type="Console" name="STDOUT">
+      <Layout type="PatternLayout" pattern="%7r %-5level [%t] %-12logger{0} %msg%n%throwable"/>
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="DENY" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="DENY" onMismatch="ACCEPT"/>
+      </Filters>
+    </Appender>
+    <Appender type="Console" name="FLOW">
+      <Layout type="PatternLayout" pattern="%C{1}.%M %m %ex%n"/><!-- class and line number -->
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="ACCEPT" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="ACCEPT" onMismatch="DENY"/>
+      </Filters>
+    </Appender>
+    <Appender type="File" name="APPSLOG" fileName="docs/apps.log">
+      <Layout type="PatternLayout">
+        <Pattern>%d %p %C{1.} [%t] %m%n</Pattern>
+      </Layout>
+    </Appender>
+  </Appenders>
+
+  <Loggers>
+
+    <Logger name="io.nosqlbench.docsys" level="info" additivity="false" specificity="trace">
+      <AppenderRef ref="APPSLOG"/>
+    </Logger>
+
+    <Root level="trace">
+      <AppenderRef ref="STDOUT"/>
+    </Root>
+
+  </Loggers>
+
+</Configuration>
\ No newline at end of file
diff --git a/virtdata-userlibs/src/main/resources/logback.xml b/virtdata-userlibs/src/main/resources/logback.xml
deleted file mode 100644
index 01e836ef0..000000000
--- a/virtdata-userlibs/src/main/resources/logback.xml
+++ /dev/null
@@ -1,15 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<configuration>
-  <statusListener class="ch.qos.logback.core.status.NopStatusListener" />
-
-  <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender" >
-    <encoder>
-      <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-    </encoder>
-  </appender>
-
-  <root level="trace">
-    <appender-ref ref="STDOUT" />
-  </root>
-
-</configuration>
\ No newline at end of file
diff --git a/virtdata-userlibs/src/test/resources/log4j-test.xml b/virtdata-userlibs/src/test/resources/log4j-test.xml
new file mode 100644
index 000000000..70176aaf6
--- /dev/null
+++ b/virtdata-userlibs/src/test/resources/log4j-test.xml
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Configuration status="debug" strict="true" name="XMLConfigTest"
+               packages="org.apache.logging.log4j.test">
+
+  <Filter type="ThresholdFilter" level="trace"/>
+
+  <Appenders>
+    <Appender type="Console" name="STDOUT">
+      <Layout type="PatternLayout" pattern="%7r %-5level [%t] %-12logger{0} %msg%n%throwable"/>
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="DENY" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="DENY" onMismatch="ACCEPT"/>
+      </Filters>
+    </Appender>
+    <Appender type="Console" name="FLOW">
+      <Layout type="PatternLayout" pattern="%C{1}.%M %m %ex%n"/><!-- class and line number -->
+      <Filters>
+        <Filter type="MarkerFilter" marker="FLOW" onMatch="ACCEPT" onMismatch="NEUTRAL"/>
+        <Filter type="MarkerFilter" marker="EXCEPTION" onMatch="ACCEPT" onMismatch="DENY"/>
+      </Filters>
+    </Appender>
+    <Appender type="File" name="APPSLOG" fileName="docs/apps.log">
+      <Layout type="PatternLayout">
+        <Pattern>%d %p %C{1.} [%t] %m%n</Pattern>
+      </Layout>
+    </Appender>
+  </Appenders>
+
+  <Loggers>
+
+    <Logger name="io.nosqlbench.docsys" level="info" additivity="false" specificity="trace">
+      <AppenderRef ref="APPSLOG"/>
+    </Logger>
+
+    <Root level="trace">
+      <AppenderRef ref="STDOUT"/>
+    </Root>
+
+  </Loggers>
+
+</Configuration>
\ No newline at end of file
diff --git a/virtdata-userlibs/src/test/resources/logback-test.xml b/virtdata-userlibs/src/test/resources/logback-test.xml
deleted file mode 100644
index 8c7d3db36..000000000
--- a/virtdata-userlibs/src/test/resources/logback-test.xml
+++ /dev/null
@@ -1,13 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<configuration>
-
-  <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
-    <layout class="ch.qos.logback.classic.PatternLayout">
-      <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
-    </layout>
-  </appender>
-
-  <root level="trace">
-    <appender-ref ref="STDOUT" />
-  </root>
-</configuration>
\ No newline at end of file