Thank you Shalin.So in a system where the indexing rate is more than 5K TPS or so the replica will never be able to recover through peer sync process.In my case I have mostly seen step 3 where a full copy happens and if the index size is huge it takes a very long time for replicas to recover.Is there a way we can configure the number of missed updates for peer sync.
Thanks, Nishanth On Wed, Jan 21, 2015 at 4:47 PM, Shalin Shekhar Mangar < shalinman...@gmail.com> wrote: > Hi Nishanth, > > The recovery happens as follows: > > 1. PeerSync is attempted first. If the number of new updates on leader is > less than 100 then the missing documents are fetched directly and indexed > locally. The tlog tells us the last 100 updates very quickly. Other uses of > the tlog are for durability of updates and of course, startup recovery. > 2. If the above step fails then replication recovery is attempted. A hard > commit is called on the leader and then the leader is polled for the latest > index version and generation. If the leader's version and generation are > greater than local index's version/generation then the difference of the > index files between leader and replica are fetched and installed. > 3. If the above fails (because leader's version/generation is somehow equal > or more than local) then a full index recovery happens and the entire index > from the leader is fetched and installed locally. > > There are some other details involved in this process too but probably not > worth going into here. > > On Wed, Jan 21, 2015 at 5:13 PM, Nishanth S <nishanth.2...@gmail.com> > wrote: > > > Hello Everyone, > > > > I am hitting a few issues with solr replicas going into recovery and then > > doing a full index copy.I am trying to understand the solr recovery > > process.I have read a few blogs on this and saw that when leader > notifies > > a replica to recover(in my case it is due to connection resets) it will > > try to do a peer sync first and if the missed updates are more than 100 > it > > will do a full index copy from the leader.I am trying to understand what > > peer sync is and where does tlog come into picture.Are tlogs replayed > only > > during server restart?.Can some one help me with this? > > > > Thanks, > > Nishanth > > > > > > -- > Regards, > Shalin Shekhar Mangar. >
