Re: imbalance in number of zookeeper clients
It (unbalanced number of clients) happens, and it's not normally a problem. In general, Accumulo is a pretty light user of zookeeper. It does add a lot of watches for table and user configuration (ACCUMULO-2757), but those things rarely change. If a particular zookeeper node is too bogged down, the clients will miss heartbeats and reconnect to another server, which will (eventually) re-balance the load. -Eric On Fri, Sep 11, 2015 at 6:21 AM, Jeff Turnerwrote: > i think ACCUMULO-3218 may have bit us two days ago, due to the first > zookeeper > in the list being unavailable. > > but, after a full restart, i don't think that situation applies - the > lighter-load zookeeper > was in the middle of the list - 600, 600, 250, 600, 600. > > thanks, > > > > On 9/10/15 8:02 PM, dlmarion wrote: > > Hey Jeff, > > Take a look at [1] and see if the zookeeper balance issue mentioned is > applicable. > > Dave > > [1] https://accumulo.apache.org/release_notes/1.6.2.html > > > > > > Original message > From: Jeff Turner > Date: 09/10/2015 7:42 PM (GMT-05:00) > To: user@accumulo.apache.org > Subject: imbalance in number of zookeeper clients > > sorry if this is a faq. i can't come up with a good google query to > find the answer. > > how bad is it that four of our five zookeepers have 600-700 clients, and > one > has about 250? > > i assumed that zookeeper or accumulo has some sort of natural > rebalancing property, > so it will all work itself out. > > i've been resisting a full accumulo/zk restart. > and restarting the one zookeeper to see what happens has a big > unpleasant wake, too. > > so >- will they eventually rebalance >- if not, how bad is it that four of them are working harder > > thanks, > jeff > > >
Re: imbalance in number of zookeeper clients
i think ACCUMULO-3218 may have bit us two days ago, due to the first zookeeper in the list being unavailable. but, after a full restart, i don't think that situation applies - the lighter-load zookeeper was in the middle of the list - 600, 600, 250, 600, 600. thanks, On 9/10/15 8:02 PM, dlmarion wrote: Hey Jeff, Take a look at [1] and see if the zookeeper balance issue mentioned is applicable. Dave [1] https://accumulo.apache.org/release_notes/1.6.2.html Original message From: Jeff TurnerDate: 09/10/2015 7:42 PM (GMT-05:00) To: user@accumulo.apache.org Subject: imbalance in number of zookeeper clients sorry if this is a faq. i can't come up with a good google query to find the answer. how bad is it that four of our five zookeepers have 600-700 clients, and one has about 250? i assumed that zookeeper or accumulo has some sort of natural rebalancing property, so it will all work itself out. i've been resisting a full accumulo/zk restart. and restarting the one zookeeper to see what happens has a big unpleasant wake, too. so - will they eventually rebalance - if not, how bad is it that four of them are working harder thanks, jeff
RE: imbalance in number of zookeeper clients
Hey Jeff, Take a look at [1] and see if the zookeeper balance issue mentioned is applicable. Dave [1] https://accumulo.apache.org/release_notes/1.6.2.html Original message From: Jeff TurnerDate: 09/10/2015 7:42 PM (GMT-05:00) To: user@accumulo.apache.org Subject: imbalance in number of zookeeper clients sorry if this is a faq. i can't come up with a good google query to find the answer. how bad is it that four of our five zookeepers have 600-700 clients, and one has about 250? i assumed that zookeeper or accumulo has some sort of natural rebalancing property, so it will all work itself out. i've been resisting a full accumulo/zk restart. and restarting the one zookeeper to see what happens has a big unpleasant wake, too. so - will they eventually rebalance - if not, how bad is it that four of them are working harder thanks, jeff