users@grizzly.java.net

Re: [Fwd: Glassfish, Comet, AJAX]

From: John Portnov <j.portnov_at_gmail.com>
Date: Tue, 24 Mar 2009 11:48:53 -0400

Jeanfrancois,

Are you saying that you do not need a streaming server or Flash server to
stream video files? I would love to see a working example of pushing wmv
and flv files via comet to the client. If you say it will work the same
way, then it should also play while frames are being pushed to the client
without any breaks/delays in the media player or Flv Player. If that is
true, please show me how?

There is a big difference between download and streaming frames of video.
Regardless of push or pull technology, download is download while streaming
video is completely different concept. My question was about streaming
video, not how Comet is better for pushing data to the client with thread
usage.

My questions still stands?

John

On Tue, Mar 24, 2009 at 10:35 AM, Jeanfrancois Arcand <
Jeanfrancois.Arcand_at_sun.com> wrote:

> Salut,
>
> John Portnov wrote:
>
>> Jeanfrancois,
>> I was told that Comet is used for pushing data to the client, not for
>> streaming video to the client. I understand how Comet can be used for data,
>> from the presentation, but even Doris said that Comet is not meant to be
>> used for streaming video. If you know different, please elaborate?
>>
>
> When streaming video, you usually reserve a Thread which stream the data.
> If the remote client is slow or some trafic on the network, that Thread may
> spend more time that it should to stream. For 10 clients no issues but for
> 10 000 you don't want to waste any Thread. Hence using Comet you can reduce
> the number of "wasted" Thread by making sure a Thread write only when it is
> garantee the bytes will be written, reducing the probability the Thread
> "hangs" or wait for the network/client to read the bytes. So Comet can be a
> nice technology for streaming in that sense.
>
> Does that help?
>
> Thanks
>
> -- Jeanfrancois
>
>
> John
>>
>> On Tue, Mar 24, 2009 at 10:05 AM, Jeanfrancois Arcand <
>> Jeanfrancois.Arcand_at_sun.com <mailto:Jeanfrancois.Arcand_at_sun.com>> wrote:
>>
>> Salut,
>>
>>
>> doris chen wrote:
>>
>> Hi,
>> I did a comet presentation for CommunityOne in New York last
>> week. The session is very well received. One of the attendees
>> asked me the following question (see his email below). Do we
>> have any suggestion for him?
>>
>>
>> Thanks Doris! Response inline.
>>
>>
>>
>> Thanks,
>>
>> Doris
>>
>> -------- Original Message --------
>> Subject: Glassfish, Comet, AJAX
>> Date: Fri, 20 Mar 2009 13:01:15 -0400
>> From: John Portnov <j.portnov_at_gmail.com
>> <mailto:j.portnov_at_gmail.com>>
>> To: Doris.Chen_at_Sun.COM
>>
>>
>>
>> Doris,
>> It was a pleasure meeting you. Your presentation was the best.
>> I really enjoyed your presentation and the content.
>> You said that you would follow up to determine how to stream
>> wmv files, in addition to flv files to the browser. I think a
>> Streaming Server may be required for wmv files, but not for flv
>> files. I understand that COMET cannot be used for video
>> streaming, and I am looking for a solution.
>>
>>
>> Why do you think Comet cannot be used. Grizzly Comet supports
>> asynchronous write, which is quite helpful when it is time to write
>> large chunk of data without having a thread that block.
>>
>> Thanks!
>>
>> -- Jeanfrancois
>>
>>
>>
>> Any ideas/suggestions would be helpfull. Also, can you please
>> send me the link to your presentation?
>> Thanks in advance,
>> John Portnov
>>
>>
>>