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I'm seeing some weird behaviour with FileDescriptorEvents. Consider this reduced example for vibed 0.7.20:

module main;

import core.sys.posix.sys.socket, core.sys.posix.fcntl;
import std.datetime, std.stdio;
import vibe.d;

void main()
{
    auto c = new C();
    runTask(&c.test);
    setIdleHandler(&c.idle);
    runEventLoop();
}

class C
{
    bool idle()
    {
        static SysTime time;
        writeln(Clock.currTime - time);
        time = Clock.currTime;
        return false;
    }

    void test()
    {

        auto address = resolveHost("google.com", AF_INET, true);
        address.port = 80;
        auto fd = socket(address.family, SOCK_STREAM, 0);
        auto flags = fcntl(fd, F_GETFL, 0);
        flags = flags | O_NONBLOCK;
        assert(fcntl(fd, F_SETFL, flags) == 0);
        connect(fd, address.sockAddr, address.sockAddrLen);
        auto _watcher = createFileDescriptorEvent(fd,FileDescriptorEvent.Trigger.any);
        _watcher.wait(dur!"seconds"(30));
    }
}

When I run this the idle handler is called with very small delays (~3 μs) for some time and the OS task manager shows 100% CPU consumption. If I use FileDescriptorEvent for real I/O operations I see 100% CPU load all the time.

With this simple example the CPU load normalizes after a few seconds but with more complicated examples I also managed to keep the CPU busy even after all tasks have finished. I can't seem to reproduce that now though.

OS is linux x86_64, compilers dmd 2065 or gdc 2064, libevent backend, vibed 0.7.20.

Is there anything wrong with the way I'm using FileDescriptorEvent or is this some kind of bug?