logging - monitor log4j behaviour under load -


i want test j2ee application under high load of sessions accessing different pages.

this web application uses log4j log bunch of errors,warnings , infos. want test side effect of load on writing log files, concurrent i/o writing actions.

i found log4j deadlock under high load conditions.

the question os (linux) has limitation on concurrent i/o file writing or log4j handle concurrency?

how can monitor i/o process delays (because of high load) or deadlock happens?

thanks

as nobody answered question,

this link somehow me through solving problem.

log4j writes files , console serially. while 1 thread writing thread wants write has wait until other 1 finished. also, stdout can block if whatever attached on other end not draining it.

in unix there special file descriptor called stdout. when start applications in console stdout attached console. can redirect stdout other files. ex: java blah > /dev/null. chances have stdout pointing file filling up. example pipe file , if program @ other end isn't draining pipe program writing pipe block.


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