On Thu, Sep 12, 2013 at 12:05 AM, Rakesh R <[email protected]> wrote: > AFAIK, ping requests would not involve any disk I/O, but it would go through > the RequestProcessor chain and executes sequentially.
Yes, that's what I meant. Ping requests don't touch disk, but they do go through the commit processor. So if a ping request is behind a write operation that takes a long time, the ping request will be affected. This is done intentionally to take the disk into account for the heartbeat mechanism. Anyways, I misunderstood what Jeremy was proposing. He wants to keep the session timeout relatively high to tolerate slow disk, but at the same time detect non-disk failure (node down, network partition) more quickly. I think this can be done purely on the client side. Create a separate thread that sends a 4 letter word command like ruok periodically, and close the socket if the client doesn't get the response within certain amount of time.
