Hi, according to https://logging.apache.org/log4j/2.x/performance.html logging with location information should be roughly the same performance for JUL and Log4j2.
However I made a few comparisons between Log4j2 and JUL and in this case Log4j2 is much faster than JUL when omitting location information, but is considerably slower when logging with location information. Those are the results: JUL without location information : 32.162s JUL with location information : 21.682s Log4j2 without location information: 4.168s Log4j2 with location information : 59.000s In each case I logged 1500000 simple log statements (only a fixed string) and compared the timestamp of the first and the last generated log statement. Above you see the time spent between the first and the last log statement. I did these tests several times and the results are equal each time. In all cases I logged to a RollingFileAppender (or JULs equivalent). I assume that JUL with location information is faster than JUL without location information is because for JUL with location information I used a custom Formatter that doesn't support any configuration whereas I was using a SimpleFormatter with a specified formatstring for JUL without log information. It should be noted that I didn't use the Log4j2 API, but instead used the JUL logging API and used the log4j-jul-bridge to actually use Log4j2 instead of the JUL implementation! I want to pay special attention to the difference when logging with location information, since I am puzzled that Log4j2 is that much slower than JUL in that case. The implementation of my custom Formatter is this: public class OneLineFormatter extends Formatter { private static final String LINE_SEPARATOR = System.getProperty("line.separator"); private static final DateFormat DATE_FORMAT= new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSSS"); @Override public String format(final LogRecord record) { final StringBuilder sb = new StringBuilder(); final String dateString= DATE_FORMAT.format(new Date(record.getMillis())); sb.append(dateString) .append(" ") .append(getLogLevelString(record.getLevel())) .append(" [") .append(record.getSourceClassName()) .append("#") .append(record.getSourceMethodName()).append("()") .append("]") .append(" - ") .append(formatMessage(record)) .append(LINE_SEPARATOR); if (record.getThrown() != null) { try { StringWriter sw = new StringWriter(); PrintWriter pw = new PrintWriter(sw); record.getThrown().printStackTrace(pw); pw.close(); sb.append(sw.toString()); } catch (Exception ex) { // ignore } } return sb.toString(); } private String getLogLevelString(final Level level){ return String.format("%1$-7s", level.getName()); } } The log4j2 configuration I used is this: <Configuration monitorinterval="30" status="info" strict="true"> <Properties> <Property name="filename">logs/log4j2-with-method.log</Property> <Property name="filepattern">logs/log4j2-with-method.log.%i.gz</Property> </Properties> <Appenders> <Appender type="RollingFile" name="File" fileName="${filename}" filePattern="${filepattern}" bufferedIO="true"> <Policies> <OnStartupTriggeringPolicy /> <SizeBasedTriggeringPolicy size="100mb"/> </Policies> <DefaultRolloverStrategy max="15" fileIndex="min" /> <Layout type="PatternLayout" pattern="%d %-6p [%C#%M] (%t) %m %ex%n" /> </Appender> </Appenders> <Loggers> <Root level="INFO"> <AppenderRef ref="File" /> </Root> <Logger name="LPT_SIMPLE" level="ALL" /> </Loggers> </Configuration> I don't think there is anything special. Since when logging without location information Log4j2 is much faster than JUL there must be a difference between getting the location information. My above mentioned custom formatter uses the methods java.util.LogRecord#getSourceClassName() and java.util.LogRecord#getSourceMethodName() for obtaining that information. I haven't looked into how Log4j2 does it, but it seems to be much less efficient. Can someone explain why Log4j2 is that much slower in that case? Is there another way in Log4j2 to get the location information that performs as fast as JUL? Best regards Marco --------------------------------------------------------------------- To unsubscribe, e-mail: log4j-user-unsubscr...@logging.apache.org For additional commands, e-mail: log4j-user-h...@logging.apache.org