On Tue, 2016-06-21 at 08:28 -0400, Benson Margulies wrote: > Oleg, If I set a TTL, do I also need an IdleConnectionMonitorThread ( > http://hc.apache.org/httpcomponents-client-ga/tutorial/html/connmgmt.html#d5e652 > )? thanks, benson. >
TTL setting only ensures connections cannot get re-used beyond their TTL but they can still be kept alive in the pool until the pool manager discards them either while trying to find a valid connection or while evicting expired ones. One might still need IdleConnectionMonitorThread to ensure eviction of expired connections when the connection manager becomes idle after a period of heavy activity. Oleg > > On Tue, Jun 21, 2016 at 4:41 AM, Oleg Kalnichevski <ol...@apache.org> wrote: > > On Mon, 2016-06-20 at 13:57 -0400, Benson Margulies wrote: > >> We use the async http components library to connect various components > >> in a system that is deployed, in some cases, on AWS. When it's > >> deployed on AWS, there are ELBs involved. > >> > >> Like some other people, we've having various trauma dealing with the > >> very dynamic environment of AWS ELBs, which includes constant DNS > >> changes and some other issues. So far, we've been making our HC > >> configuration more and more complex. I'm wondering if we should back > >> off and make it simpler -- make a new connection for each request. > >> Obviously, this will be somewhat slower and more expensive, but at the > >> moment we might prefer a slower and more expensive approach that works > >> to one that occasionally gets lost. > >> > >> I appreciate that even making new connections all the time won't > >> compensate for all possible DNS problems -- if Java itself caches a > >> stale name->address translation, making a new connection will fail > >> just as effectively as anything else. > >> > >> Does anyone out there have advice to share (other than running away from > >> ELB)? > >> > > > > Hi Benson > > > > I personally would consider disabling connection persistence extreme and > > unnecessary. Consider setting the TTL (total time to live) of persistent > > connections to some low value (say, 10 seconds or even less) instead. > > This should improve distribution of connections across the cluster of > > servers behind a load balancer. > > > > Hope it helps > > > > Oleg > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: httpclient-users-unsubscr...@hc.apache.org > > For additional commands, e-mail: httpclient-users-h...@hc.apache.org > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: httpclient-users-unsubscr...@hc.apache.org > For additional commands, e-mail: httpclient-users-h...@hc.apache.org > --------------------------------------------------------------------- To unsubscribe, e-mail: httpclient-users-unsubscr...@hc.apache.org For additional commands, e-mail: httpclient-users-h...@hc.apache.org
