I think Client is intended to be thread-safe, but it isn't currently,
because the connectTimeout field is not guarded by a lock (nor is it
volatile) -- sorry Jerome, I just noticed this. This is not likely to cause
any problems, but it *is* wrong.
And there may be other concurrency issues lurking in Client. My feeling is
better safe than sorry. If you really need to have multiple threads talking
to a Client instance -- and it's not clear to me that you do -- use a
ThreadLocal<Client>. It might be unnecessary, but it limits the number of
open file handles to some small factor of the number of threads talking to
Clients simultaneously.
--tim
On Wed, Oct 15, 2008 at 10:14 PM, Sanjay Acharya <[EMAIL PROTECTED]>wrote:
> Hi Jerome,
>
> I believe I have found the cause of our problem.
>
> We use Restlet Client by instantiating it every time, for example,
>
> for (int i = 0; i < 10000000; i++) {
> Client c = new Client();
> ....
> Response response = c.handle(request);
> response.release();
>
> }
>
> we end up creating a downstream HttpClient on every client. When release()
> is called, the socket connection is released back to the
> HttpConnectionManager.
> HttpConnectionManager does not close the socket. However, due to garbage
> collection, at some point the underlying socket is closed out.
> It happens some times and not others, i.e., via the luck of GC running.
>
> If we however, hold a Reference of every client that is instantiated, then
> we can easily reproduce the open file handle issue as GC will not free the
> underlying socket
> and we can see eventually reach a point where all the available file
> handles are consumed.
>
> That said, the direction of preference seems to point to using a single
> instance of Restlet's Client class and setting the "maxConnectionsPerHost"
> to some
> appropriate value. One concern that I have is whether Restlet's Client is
> designed to be thread safe so that multiple threads can utilize the same
> instance?
> In other words, is singleton usage the recommended pattern for using the
> client?
>
> Thanks much,
> Sanjay
>
>
>
>
> ------------------------------
>
> > From: [EMAIL PROTECTED]
> > To: [email protected]
> > Date: Wed, 15 Oct 2008 08:46:06 +0200
> > Subject: RE: Assistance and Question
> >
> >
> > Hi Sanjay,
> >
> > As a first step, I would highly recommend moving to 1.1 RC2 or a more
> recent
> > snapshot. There is a good chance that it will fix your issue.
> >
> > If not, we'll investigate more.
> >
> > Best regards,
> > Jérôme Louvel
> > --
> > Restlet ~ Founder and Lead developer ~ http://www.restlet.org
> > Noelios Technologies ~ Co-founder ~ http://www.noelios.com
> >
> >
> > -----Message d'origine-----
> > De : Sanjay Acharya [mailto:[EMAIL PROTECTED]
> > Envoyé : mercredi 15 octobre 2008 02:39
> > À : [email protected]
> > Objet : Assistance and Question
> >
> >
> > Hi,
> >
> > I am using Restlet version 1.1 m1. There are times when we run out of
> open
> > file handles in stage environment with "too many open file handles"
> error. I
> > am also using the JaxbRepresentation to marshall the data.
> > I am trying to recreate the issue related to
> > http://restlet.tigris.org/issues/show_bug.cgi?id=439 and not sure how to
> do
> > the same. I would like to be able to recreate a state where connections
> are
> > left in
> > "CLOSE_WAIT and FIN_WAIT_2 state" by the client.
> >
> > I have limited the number of open file handles to 200 for the user.
> >
> > Any assistance to be able to duplicate the issue would be great.
> > Thanks,
> > Sanjay
> >
> > Code on Resource class:
> > @Override public void post(Representation representation) {
> >
> > String greeting = "Hello thgere";
> >
> > Person p = new Person();
> > p.setFirstName("Foo");
> > p.setLastName("Bar");
> >
> > // A Large address list
> > p.setAddresses(buildAddress());
> > SayHelloResponse resp = new
> > SayHelloResponse().withPerson(p).withGreeting(greeting);
> >
> > JaxbRepresentation responseRep = new
> > JaxbRepresentation(MediaType.APPLICATION_XML, resp);
> >
> > getResponse().setEntity(responseRep);
> >
> > getResponse().setStatus(Status.SUCCESS_OK);
> > }
> >
> > Code on Client class:
> > Person p = new Person()....
> > ....
> > SayHelloRequest sayHelloRequest = new
> SayHelloRequest().withPerson(person);
> >
> > Request restRequest = createRequest();
> > request.setEntity(new JaxbRepresentation(MediaType.APPLICATION_XML,
> > sayHelloRequest));
> > Response response = client.handle(restRequest);
> > response.getEntity().release();
> > _________________________________________________________________
> > See how Windows connects the people, information, and fun that are part
> of
> > your life.
> > http://clk.atdmt.com/MRT/go/msnnkwxp1020093175mrt/direct/01/=
> >
>
>
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