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Migrating JUL to log4j2, performance is not as expected. What went wrong?

I am a new user of log4j2. Based on Log4j2 performance tests introduction, and it may need to generate a large number of csv files for data processing. I plan to migrate a project from JUL to log4j2. This is a multi-threaded project that uses a lot of loggers. But the test results are not satisfactory . Where did I get it wrong?
the compare results
The dependency configuration is as follows:
<!-- Log4j2 api -->
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-api</artifactId>
<version>2.11.1</version>
</dependency>
<!-- Log4j2 impl.-->
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-core</artifactId>
<version>2.11.1</version>
</dependency>
<!-- for Log4j2 asynchronous logging-->
<dependency>
<groupId>com.lmax</groupId>
<artifactId>disruptor</artifactId>
<version>3.4.2</version>
</dependency>
<!-- for Log4j2 csvlayout-->
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-csv</artifactId>
<version>1.5</version>
</dependency>
File "log4j2.xml" has multiple similar appenders and loggers, for example:
partial configuration for log4j2.xml
Java related code is as follows:
System.setProperty("log4j2.isThreadContextMapInheritable", "true");
String renameCsvFile = new String( inputDir.getName() + StaticUtils.SEPARATOR +"log"+ StaticUtils.SEPARATOR + "rename");
ThreadContext.put("module3", renameCsvFile);
rename_logger = LogManager.getLogger("myrenamelog");
rename_logger.info("rename logging", "Timestamp","Level", "OrignalPath","RenamedPath","Status", "Message", "Layer#", "Thread#");
rename_logger.info("rename logging...", Instant.now(),"info",file.getAbsolutePath(),newName.getAbsolutePath(),"success"," ","Layer#",Thread.currentThread().getName());

I would suggest you upgrade to the latest release. Specifically, LOG4J2-2644, which was addressed in Log4j 2.12.1, should impact some of your performance times. However, as in LOG4J2-2792, some applications that rely heavily on filters might need to disable eagerly obtaining the location.
If after testing with a newer version you still have problems please create a Jira issue with Log4j. Ideally you should either provide a sample test suite to demonstrate the problem and/or a snapshot created with a profiling tool such as YourKit that can help identify the problem areas.

How to set the variable instrumentationKey for azure monitoring in a spring boot application

I have a issue to setup azure monitoring in spring boot project.
i have the error at each start:
instrumentationKey must be set to report metrics to Azure Monitor.
i have set the application.properties with the following properties:
azure.application-insights.instrumentation-key=VALID-UUID
spring.application.name=test
the dependency of the project looks like:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>2.1.3</version>
</dependency>
<dependency>
<groupId>com.microsoft.azure</groupId>
<artifactId>azure-spring-boot-metrics-starter</artifactId>
<version>2.1.4</version>
</dependency>

As per this https://learn.microsoft.com/en-us/azure/azure-monitor/app/micrometer-java#using-spring-2x documentation you need to add application-insights-springboot-starter as well.
Otherwise, you can set key as azuremonitor.instrumentationKey. My recommendation would be to add application-insights-springboot-starter along with azure-spring-boot-metrics-starter

Tracing by dependency
azure-spring-boot-metrics-starterazure-spring-boot-metrics-starter -->
micrometer-registry-azure-monitor -->
com.microsoft.azure:applicationinsights-core
Your error message come from AzureMonitorConfig
So I think the key be modify to
azuremonitor.instrumentationKey

Difference between slf4j-log4j12 vs log4j

In a project's pom.xml I am seeing a dependency like below
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.5</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
Can someone let me know what is the difference between slf4j-log4j12 & log4j ?

Log4j 1.2
slf4j-log4j12 provides a bridge between SLF4J and Log4j 1.2 so that SLF4J knows about how to log using Log4j.
You are using Log4j 1.2. That version's binding it is maintained by the SLF4J project. Here is a summary from the SLF4J docs:
SLF4J supports various logging frameworks. The SLF4J distribution ships with several jar files referred to as "SLF4J bindings", with each binding corresponding to a supported framework.
slf4j-log4j12-1.7.28.jar
Binding for log4j version 1.2, a widely used logging framework. You also need to place log4j.jar on your class path.
Log4j 2
If you are using Log4j 2 or later, you will need a different binding JAR than slf4j-log4j12. That binding is maintained by the Log4j project. According to the Log4j docs:
The Log4j 2 SLF4J Binding allows applications coded to the SLF4J API to use Log4j 2 as the implementation.
You must provide both dependencies if you want SLF4J to route logging to Log4j. Again, from the Log4j 2 docs:
Simply include the Log4j 2 SLF4J Binding jar along with the Log4j 2 jars and SLF4J API jar to cause all SLF4J logging to be handled by Log4j 2.

To summarize:
<dependency> <!--Facade for logging systems-->
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.25</version>
</dependency>
<dependency> <!--Log4j 2 implementation for slf4j-->
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-slf4j-impl</artifactId>
<version>2.12.0</version>
</dependency>
In addition make sure that you are using a log4j2 properties file. The mistake of using 'log4j.xml' did cost me quite some time

I'll post some points regarding these logger message.
log4j:
logger.debug("This is log message:" + msg);
log4j string is concatenated every time the line is evaluated even if log level is lower than debug so the string will never be used.
slf4j:
logger.debug("this is log slf4j message",msg);
slf4j string and parameters are passed through to the logger which only substitutes them if the log message is actually to be used.
The only difference is the performance. Where log4j will take more time because of string concatenation compare to slf4j.

Slf4j:
An abstract layer for the logging component.
We can change logging at point of time without much changes in code.
Log4j:
A logging component which provides core functionalities of logging.

adding jXLS to my pom.xml seems to affect hibernate log level

Adding jXLS to my pom seems to affect my app Hibernate log level. The app will log hibernate DEBUG info at every second in the tomcat console (using eclipse).
I add these two dependencies:
<dependency>
<groupId>org.jxls</groupId>
<artifactId>jxls</artifactId>
<version>2.2.5</version>
</dependency>
<dependency>
<groupId>org.jxls</groupId>
<artifactId>jxls-jexcel</artifactId>
<version>1.0.3</version>
</dependency>
When I remove both, then everything will be ok. If I add any of them, then I get the DEBUG info in the console again.
Any idea why is this happening?! Logger is Log4j.

I found an answer in this post:
Disable logging with hibernate from maven
Adding file logback.xml with the described content solved hibernate logging problem.

How to use and configure logback in Adobe CQ5 projects?

I newbie in CQ5. I started my first project in CQ and I want to write any exceptions and debug info of project's components, services and servlets (in bundles) to log files in crx-repo (...\crx-quickstart\logs).
I want to use slf4j with logback implementation in my project.
I tried below steps:
Add dependencies in project's pom.xml
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.7</version>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.1.3</version>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-core</artifactId>
<version>1.1.3</version>
</dependency>
Add logback.xml with configuration (loggers and appenders) to
project's bundle resource package.
Try to instantiate new logger in service (for example):
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
.....
#Component(metatype = true, label = "Some", description = "Sone service" ,
immediate = true)
#Service(SomeService.class)
public class SomeService {
private final Logger logger = LoggerFactory.getLogger(MyDao.class);
.....
logger.debug("debug");
logger.info("info");
logger.error("error");
......
}
These steps (It isn't work, of course) I gave an example because i don't know how really work with logback in Adobe CQ5. Any suggestions? I would be grateful for any help!

CQ does log to crx-quickstart/logs/error.log with its default configuration, and the underlying Apache Sling framework provides the necessary bridge so you just need to acquire an slf4j Logger and write to that.
The Java code of your SomeService example looks correct to me but in the pom you only need the slf4j-api dependency, with scope provided, as API and implementation packages are provided by the CQ runtime.
You can also have a look at a Sling sample like Slingbucks which will log to that error.log if installed on a default CQ instance.