I’m developing an application that consumes result of command ssh -p29418 [email protected] gerrit stream-events -s comment-added.
This command output events as json, one event per line.

{"type":"comment-added",change:{"project":"tools/gerrit", ...}, ...}

Here’s an example code of my application.

// A ssh client library
Jsch client = new JSch();
Session session = client.getSession("username", "host", 22);
session.setPassword("password");
session.connect();

ChannelExec channelExec = (ChannelExec) session.openChannel("channelExec");
channelExec.setCommand("gerrit stream-events -s comment-added");
channelExec.connect();

InputStreamReader reader = new InputStreamReader(channelExec.getInputStream());
BufferedReader bufferedReader = new BufferedReader(reader);

String event;
while ((event = bufferedReader.readLine()) != null) {
    handleEvent(event);
}

As a constract, i started two instance of this application (first instance handleEvent method return in 1s, second instance handleEvent return in 20s). Imaging that after a long time running, the first instance recorded all events sent by server, but the second instance lost event randomly, is this possible?

1. What will happen to the event producer when consumer consume events (the second app) slower than producer (gerrit stream-events)?
2. I’ve read some pages explaining that the socket sender cannot continue send bytes until the socket receiver’s recv_buf has enough spaces. Does this limitation will block process output message to stdout?
3. What’s the difference between socket write_buf and java program System.out’s write_buf? What will happen if java program stdout be redirected to socket output but sender write_buf and receiver recv_buf is full?
4. How does ssh server-side redirect stdout of command gerrit stream-events and deliver to client-side.