diff options
| -rw-r--r-- | ev.pod | 29 |
1 files changed, 19 insertions, 10 deletions
@@ -3242,16 +3242,22 @@ And a F<ev_cpp.C> implementation file that contains libev proper and is compiled =head2 THREADS -Libev itself is completely thread-safe, but it uses no locking. This -means that you can use as many loops as you want in parallel, as long as -only one thread ever calls into one libev function with the same loop -parameter. - -Or put differently: calls with different loop parameters can be done in -parallel from multiple threads, calls with the same loop parameter must be -done serially (but can be done from different threads, as long as only one -thread ever is inside a call at any point in time, e.g. by using a mutex -per loop). +Libev itself is thread-safe (unless the opposite is specifically +documented for a function), but it uses no locking itself. This means that +you can use as many loops as you want in parallel, as long as only one +thread ever calls into one libev function with the same loop parameter: +libev guarentees that different event loops share no data structures that +need locking. + +Or to put it differently: calls with different loop parameters can be done +concurrently from multiple threads, calls with the same loop parameter +must be done serially (but can be done from different threads, as long as +only one thread ever is inside a call at any point in time, e.g. by using +a mutex per loop). + +Specifically to support threads (and signal handlers), libev implements +so-called C<ev_async> watchers, which allow some limited form of +concurrency on the same event loop. If you want to know which design (one loop, locking, or multiple loops without or something else still) is best for your problem, then I cannot @@ -3280,6 +3286,9 @@ better than you currently do :-) event loop - C<ev_async> watchers can be used to wake them up from other threads safely (or from signal contexts...). +=item * some watcher types are only supported in the default loop - use +C<ev_async> watchers to tell your other loops about any such events. + =back =head2 COROUTINES |