- Use readonly object as lock
Info from stackoverflow:
If I want to be sure that it will be locked for all threads inside my
application:
The lock object has to be static, if it locks access to static state.
Otherwise it has to be instance, because there's no need to lock state of
one class instance, and prevent other threads to work with another class
instance at the same time.
everyone says that the object has to be "readonly" I didn't found the
reason
Well, it doesn't have to be. This is just a best practice, which helps you
to avoid errors.
Signed-off-by: Syrone Wong <wong.syrone@gmail.com>
after creation.
Becuase we put handler.Start() call after timeout check and
lastActivity is initialized in Start(), this will lead to a
incorrect timeout.
Also because we will call handler.Start() right after the
constructor and timeout check, so it makes no difference
where we put the initializtion of lastActivity. We won't do
this again in Start() because DateTime.Now will consumes a
lot of cpu time.
When using http proxy, this will cause distinct latency
if we are trying to resolve localhost.
Currently it's unnecessary to do that because our privoxy
doesn't listern on ipv6 address, so it's ok to hard code
the ipv4 address.
There is a plan to add a cache to record the ipv6 connectivity
so that we needn't to try both ipv4 and ipv6 every time when we
attempt to connect a DnsEndPoint.
Lock is evil.
This will actually affect the accuracy of GetDelta because
inboundDelta and outboundDelta may be calculated based on
the data collected at different time (eg. UpdateOutbound
get called before Interlocked.Read(ref _outbound)).
But that's not a problem. We can tolerate this little
inaccuracy. Besides, the _inbound, _outbound, _lastInbound
and _lastOutbound will be totally good because we use Interlocked.
To prevent "The IAsyncResult object was not returned from
the corresponding asynchronous method on this class." exception.
Signed-off-by: noisyfox <timemanager.rick@gmail.com>
noisyfox
Syrone Wong