Hi,I use jprofiler to monitor appliaction,the result shows that,at the same time only on thread is runing,the others are blocked,why? pls see attachment,thanks.
2010-12-17 刘东 发件人： 刘东 发送时间： 2010-12-17 10:51:48 收件人： Log4J Users List 抄送： 主题： Re: RE: Re: performance problem in multithread environment Hi,thank you very much. I test asyncappender again,the result is as follows: thread number |time cost |asyn BufferSize 1 |28282 |1024 2 |56359 |1024 4 |107188 |1024 16 |421547 |1024 my log4j.xml is: <?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE log4j:configuration PUBLIC "-//log4j/log4j Configuration//EN" "log4j.dtd"> <log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/";> <appender name="file-log" class="org.apache.log4j.RollingFileAppender"> <param name="bufferSize" value="262144" /> <param name="bufferedIO" value="true" /> <!-- <param name="fileAppend" value="true" /> --> <param name="File" value="log4jtest.log" /> <layout class="org.apache.log4j.PatternLayout"> <param name="ConversionPattern" value="%-d{yyyy-MM-dd HH:mm:ss} [%-5p] [%t] [%c.%M:%L] - %m%n" /> </layout> </appender> <appender name="async" class="org.apache.log4j.AsyncAppender"> <param name="BufferSize" value="1024" /> <appender-ref ref="file-log" /> </appender> <!-- for all other loggers log only debug and above log messages --> <root> <priority value="DEBUG" /> <!-- <appender-ref ref="STDOUT" /> --> <!-- <appender-ref ref="file-log" /> --> <appender-ref ref="async" /> </root> </log4j:configuration> I turned asyn BufferSize to 10240,but the test result is no changing. why? 2010-12-17 刘东 发件人： Sebastien Tardif 发送时间： 2010-12-17 02:32:38 收件人： 'Log4J Users List' 抄送： 主题： RE: Re: performance problem in multithread environment File IO is slow, you need to have a asyncappender between your application and file i/o. -----Original Message----- From: 刘东 [mailto:betterjo...@hotmail.com] Sent: Thursday, December 16, 2010 10:02 AM To: Log4J Users List Subject: Re: Re: performance problem in multithread environment tanks for you reply. I write test program to show my appliaction case. package com.iss.cnooc.test.ebank; import org.slf4j.Logger; import org.slf4j.LoggerFactory; public class LoggerTest { Logger logger = LoggerFactory.getLogger(LoggerTest.class); public static void main(String[] args) { int i = 0; while (i < 2) { LoggerThread t = new LoggerThread(); t.start(); i++; } } } package com.iss.cnooc.test.ebank; import org.slf4j.Logger; import org.slf4j.LoggerFactory; public class LoggerThread extends Thread { Logger logger = LoggerFactory.getLogger(LoggerThread.class); @Override public void run() { int i = 0; long start = System.currentTimeMillis(); while (i < 1000000) { logger.debug("i = " + i); i++; } long ecl = System.currentTimeMillis() - start; System.out.println(this.getName() + "-" + this.getId() + " spend " + ecl); } } The test reslut is thread number | cost 1 | 46859 2 | 96593 4 | 196921 16 | 717703 I use fileappender. why? 2010-12-16 刘东 发件人： Curt Arnold 发送时间： 2010-12-16 14:15:03 收件人： Log4J Users List 抄送： 主题： Re: performance problem in multithread environment On Dec 13, 2010, at 10:54 AM, Jacob Kjome wrote: > You will get better performance by not logging at all, no question. However, there are tuning possibilities. I see you mention "logger.info()". In production, I generally only have "warn()" and above for the vast majority of loggers. In fact, I configure the root logger up with the "WARN" level and selectively set other loggers to something less than WARN (if need be). > > The other thing you might look at is whether you are concatenating strings in your logging statements. For instance the following will incur an unnecessary cost in concatenating strings even when the "DEBUG" level is not enabled.... > > logger.debug("product: " + someProduct + ", price: " + somePrice); > > A more efficient way to define this in your code is.... > > if (logger.isDebugEnabled()) { > logger.debug("product: " + someProduct + ", price: " + somePrice); > } > alternatively use LogMF or LogSF (in the extras companion or in the SVN HEAD) LogMF.debug(logger, "product: {0}, price: {1}", price,somePrice); will have performance generally comparable to using logger.isDebugEnabled when logging is disabled since any conversion and concatenation is deferred until after the logging level is checked. --------------------------------------------------------------------- To unsubscribe, e-mail: log4j-user-unsubscr...@logging.apache.org For additional commands, e-mail: log4j-user-h...@logging.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: log4j-user-unsubscr...@logging.apache.org For additional commands, e-mail: log4j-user-h...@logging.apache.org
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