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Nick Williams commented on LOG4J2-479: -------------------------------------- In my opinion, we need to take one of two paths: #Remove uses of {{InheritableThreadLocal}} completely. #Make a system option to enable use of {{InheritableThreadLocal}}, but *disable it by default* so that values are not inherited unless specifically enabled. In applications that use thread pools to spin off long-running processes (and this is a lot of applications), an {{InheritableThreadLocal}} is *dangerous*. Before the thread pool is used for the first time, it is initially empty. It hasn't yet created any threads. If a thread sets the value in an {{InheritableThreadLocal}} and then borrows a thread from that pool, the pool will create a thread with the same {{InheritableThreadLocal}} values. That thread will then always have that value, even after the application returns it to the pool. Even worse, in a web application multiple applications could share a single thread pool, resulting in information leaking from one application to another. > Use of InheritableThreadLocal in Map ThreadContext is dangerous and unhelpful > ----------------------------------------------------------------------------- > > Key: LOG4J2-479 > URL: https://issues.apache.org/jira/browse/LOG4J2-479 > Project: Log4j 2 > Issue Type: Bug > Reporter: MK > > Described here http://logging.apache.org/log4j/2.x/manual/thread-context.html > The use of InheritableThreadLocal creates subtle and hard to track bugs while > not really adding much useful. It is counterintuitive -- I don't see why > would anyone expect logging context to be inherited. But it breaks down > completely when used with Thread Executors. -- This message was sent by Atlassian JIRA (v6.1.5#6160) --------------------------------------------------------------------- To unsubscribe, e-mail: log4j-dev-unsubscr...@logging.apache.org For additional commands, e-mail: log4j-dev-h...@logging.apache.org