Re: About Tombstones and TTLs

Thanks a lot Alain!! This really cleared a lot of things for me. Thanks again! Shalom Sagges DBA T: +972-74-700-4035 We Create Meaningful Connections On Mon, Dec 19, 2016 at 5:58

Re: Cqlsh timeout and schema refresh exceptions

Hi Matija, I know about the API. I am using isSchemaInAgreement, but problem is that when I am giving CREATE TABLE requests quickly. its timing out after 30 seconds. Same CF creation happens successfully(with agreement) *within 2 seconds* when I give it in isolation on a fresh cluster, or after go

Re: Cqlsh timeout and schema refresh exceptions

There is an exposed API for schema agreement and I would advise you to use that if you can. Look at this JIRA ticket . On Mon, Dec 19, 2016 at 8:46 PM, Vladimir Yudovin wrote: > Regarding schema agreement - try to increase time between CF creat

RE: FW: Cassandra trigger to send notifications

Thank you both Matija and Eric. I have read somewhere about CDC but I didn’t know that it is already released. I also didn’t find good documentation of it except for the design doc and Jira ticket, where in both cases it is hard to know what really was released. As a newbie to Cassandra I will pro

Re: Cqlsh timeout and schema refresh exceptions

Regarding schema agreement - try to increase time between CF creation. Also stress-tool waits for schema, look on its code, probably it uses some methods to ensure schema distribution. Best regards, Vladimir Yudovin, Winguzone - Cloud Cassandra Hosting On Mon, 19 Dec 2016 14:35:

Re: Cqlsh timeout and schema refresh exceptions

Thanks Vladimir! Is there any known issue in 3.0.10, where creating "CF with large number of cols" or "creating large number of CFs quickly" one after other gives schema agreement issue? What other things can I try to support ~12000 CF without hitting schema agreement related issues? I can put mo

Re: Cqlsh timeout and schema refresh exceptions

>I want to dig deeper into what all things happen in C* at time of CF creation It starts somewhere in MigrationManager.announceNewColumnFamily function, I guess. >imitation of number of keyspaces which can be created. Actually it's CF limitation, not keyspaces. >if you can also poin

Re: Cqlsh timeout and schema refresh exceptions

Hi Vladimir, Thanks for the response. When I see *"**com.datastax.driver.core.ControlConnection"* exceptions, I see that keyspaces and CF are created. But when I create CF with large number of columns(2400 cols) quickly one after the other(with 2 seconds gap between CREATE TABLE queries), I get s

Re: Cqlsh timeout and schema refresh exceptions

Hi, Question: Does C* reads some schema/metadata on calling cqlsh, which is causing timeout with large number of keyspaces? A lot ). cqlsh reads schemas, cluster topology, each node tokens, etc. You can just capture TCP port 9042 (unless you use SSL) and view all negotiation between cqlsh a

Re: Multi DC Production ready Cassandra version

And all the versions of Cassandra do multiDC as long as I remember (C*0.7), probably from the very beginning :-). C*heers, --- Alain Rodriguez - @arodream - al...@thelastpickle.com France The Last Pickle - Apache Cassandra Consulting http://www.thelastpickle.com 2016-12-19 17

Re: Multi DC Production ready Cassandra version

Hi, This has been debated here many times, I recommend you do a search in the mailing list archives for more info. The community currently recommends Apache Cassandra 3.0.last or Tic Toc releases (3.X, with X > 0) ONLY if you need a specific feature from this branch AND are ready to tackle some i

Re: About Tombstones and TTLs

>From http://www.uberobert.com/cassandra_gc_grace_disables_hinted_handoff/ This is just a quick FYI post as I don't see this documented on the web > elsewhere. As of now in all versions of Cassandra a gc_grace_seconds setting > of 0 will disable hinted handoff. Basically to avoid an edge case that

Re: About Tombstones and TTLs

>> Cassandra stores hints for the lowest of gc_grace_seconds and max_hint_window_in_ms Was this a tough design decision or just a bug? It is certainly very surprising behavior. Everything that I've read leads me to believe that gc_grace_seconds was only intended to affect the treatment of *expired

Cqlsh timeout and schema refresh exceptions

Hi All, I have a 2 node cluster(32gb ram/8cpu) running 3.0.10 and I created 50 keyspaces in it. Each keyspace has 25 CF. Column count in each CF ranges between 5 to 30. I am getting few issues once keyspace count reaches ~50. *Issue 1:* When I try to use cqlsh, I get timeout. *$ cqlsh `hostnam

Re: About Tombstones and TTLs

Hi, >- Why setting gc_grace_seconds=0 will disable hints for the table? > > It was the first time I heard about this as well when Alexander told us about that. This read might be helpful http://www.uberobert.com/cassandra_gc_grace_disables_hinted_handoff/. Also Alexander I know tested it. *t

Re: About Tombstones and TTLs

Thanks for the explanation Matija, but fortunately, that I know. Forgot to mention that I'm using a multi DC cluster. I'll try to summarize just the questions I have, because my email was indeed quite long :-) - Why setting gc_grace_seconds=0 will disable hints for the table? - How can an e

Re: About Tombstones and TTLs

Hi, gc_grace_seconds is used to maintain data consistency in some failure scenarios. When manually deleting data that action creates tombstones which are kept for that defined period before being compacted. If one of the replica nodes is down while deleting data and it gets back up after the gc_gr

About Tombstones and TTLs

Hi Everyone, I was reading a blog on TWCS by Alex Dejanovski from The Last Pickle ( http://thelastpickle.com/blog/2016/12/08/TWCS-part1.html) When I got to the comments section, I didn't understand why setting gc_grace_seconds to 0 will disable hints for the associated table: *"It is a very good