Thanks, Jun. That is very helpful. However, I still have a couple of questions. "We have a min fetch rate JMX in the broker". How to find out how such min fetch rate is defined? And if replica.lag.time.max.ms is too large, what is the consequence?
Regards, Libo -----Original Message----- From: Jun Rao [mailto:jun...@gmail.com] Sent: Tuesday, August 27, 2013 12:07 AM To: users@kafka.apache.org Subject: Re: questions about ISR I added the following in FAQ: https://cwiki.apache.org/confluence/display/KAFKA/FAQ#FAQ-HowtoreducechurnsinISR%3F Thanks, Jun On Mon, Aug 26, 2013 at 7:46 PM, James Wu <jameswu...@gmail.com> wrote: > Hi Jun, > > I am curious Yu's questions too. > > 1. What is the best practice to set replica.lag.time.max.ms & > replica.lag.max.messages ? As long as possible or something else ? > > 2. If the broker exceeds one of these 2 configurations, how should we > do to bring the broker back to ISR ? Will controller automatic cover > this to catch broker up, the only thing we need to do is waiting for > the broker back ? > > Thanks. > > > > > On Mon, Aug 26, 2013 at 11:15 PM, Jun Rao <jun...@gmail.com> wrote: > > > That's right. You shouldn't need to restart the whole cluster for a > broker > > to rejoin ISR. Do you see many ZK session expirations in the brokers > > (search for "(Expired)"? If so, you may need to tune the GC on the > broker. > > > > Thanks, > > > > Jun > > > > > > On Mon, Aug 26, 2013 at 7:11 AM, Yu, Libo <libo...@citi.com> wrote: > > > > > Hi Jun, > > > > > > Could you confirm the following? > > > So after a broker is out of ISR, the only way to let it go back is > > > to restart it. > > > > > > We should set replica.lag.time.max.ms and replica.lag.max.messages > > > as large as possible to avoid a broker fall outside of ISR. > > > > > > What we have experienced is that when a broker is out of ISR > > > frequently we need to restart the whole cluster to make it back. > > > That is a > blocking > > > issue > > > for us. > > > > > > > > > Regards, > > > > > > Libo > > > > > > > > > -----Original Message----- > > > From: Jun Rao [mailto:jun...@gmail.com] > > > Sent: Friday, August 23, 2013 11:41 PM > > > To: users@kafka.apache.org > > > Subject: Re: questions about ISR > > > > > > When a broker is restarted, it will automatically catch up from > > > the > > leader > > > and will join ISR when it's caught up. Are you not seeing this > happening? > > > > > > Thanks, > > > > > > Jun > > > > > > > > > On Fri, Aug 23, 2013 at 11:33 AM, Yu, Libo <libo...@citi.com> wrote: > > > > > > > Hi, > > > > > > > > When a broker is not in a topic's ISR, will it try to catch up > > > > to go back to ISR itself? > > > > Or do we have to restart it? > > > > > > > > We can increase replica.lag.time.max.ms and > > > > replica.lag.max.messages to let brokers stay longer in ISR. Is > > > > that good practice? Still this is related to the first > > > > questions. We want to know what happens after a broker falls out of ISR > > > > and what we should do. Thanks. > > > > > > > > > > > > Regards, > > > > > > > > Libo > > > > > > > > > > > > > > > > > -- > > Friendly regards, > > *James Wu <https://plus.google.com/u/0/100829801349304669533> > * >
