Data Corruption due to multiple Cassandra 2.1 processes?

2018-08-06 Thread Steinmaurer, Thomas
Hello, with 2.1, in case a second Cassandra process/instance is started on a host (by accident), may this result in some sort of corruption, although Cassandra will exit at some point in time due to not being able to bind TCP ports already in use? What we have seen in this scenario is

Re: Hinted Handoff

2018-08-06 Thread kurt greaves
> > Does Cassandra TTL out the hints after max_hint_window_in_ms? From my > understanding, Cassandra only stops collecting hints after > max_hint_window_in_ms but can still keep replaying the hints if the node > comes back again. Is this correct? Is there a way to TTL out hints? No, but it won't

Re: Bootstrap OOM issues with Cassandra 3.11.1

2018-08-06 Thread Jeff Jirsa
Upgrading to 3.11.3 May fix it (there were some memory recycling bugs fixed recently), but analyzing the heap will be the best option If you can print out the heap histogram and stack trace or open a heap dump in your kit or visualvm or MAT and show us what’s at the top of the reclaimed

Re: Bootstrap OOM issues with Cassandra 3.11.1

2018-08-06 Thread Jeff Jirsa
Are you using materialized views or secondary indices? -- Jeff Jirsa > On Aug 6, 2018, at 3:49 PM, Laszlo Szabo > wrote: > > Hello All, > > I'm having JVM unstable / OOM errors when attempting to auto bootstrap a 9th > node to an existing 8 node cluster (256 tokens). Each machine has 24

Bootstrap OOM issues with Cassandra 3.11.1

2018-08-06 Thread Laszlo Szabo
Hello All, I'm having JVM unstable / OOM errors when attempting to auto bootstrap a 9th node to an existing 8 node cluster (256 tokens). Each machine has 24 cores 148GB RAM and 10TB (2TB used). Under normal operation the 8 nodes have JVM memory configured with Xms35G and Xmx35G, and handle 2-4

Re: dynamic_snitch=false, prioritisation/order or reads from replicas

2018-08-06 Thread Kyrylo Lebediev
Thank you for replying, Alain! Better use of cache for 'pinned' requests explains good the case when CL=ONE. But in case of CL=QUORUM/LOCAL_QUORUM, if I'm not wrong, read request is sent to all replicas waiting for first 2 to reply. When dynamic snitching is turned on, "data" request is sent

Re: Hinted Handoff

2018-08-06 Thread Agrawal, Pratik
Does Cassandra TTL out the hints after max_hint_window_in_ms? From my understanding, Cassandra only stops collecting hints after max_hint_window_in_ms but can still keep replaying the hints if the node comes back again. Is this correct? Is there a way to TTL out hints? Thanks, Pratik From:

Re: Hinted Handoff

2018-08-06 Thread Kyrylo Lebediev
Small gc_grace_seconds value lowers max allowed node downtime, which is 15 minutes in your case. After 15 minutes of downtime you'll need to replace the node, as you described. This interval looks too short to be able to do planned maintenance. So, in case you set larger value for

ETL options from Hive/Presto/s3 to cassandra

2018-08-06 Thread srimugunthan dhandapani
Hi all, We have data that gets filled into Hive/ presto every few hours. We want that data to be transferred to cassandra tables. What are some of the high performance ETL options for transferring data between hive or presto into cassandra? Also does anybody have any performance numbers

Re: dynamic_snitch=false, prioritisation/order or reads from replicas

2018-08-06 Thread Alain RODRIGUEZ
Hello, > There are reports (in this ML too) that disabling dynamic snitching > decreases response time. I confirm that I have seen this improvement on clusters under pressure. What effects stand behind this improvement? > My understanding is that this is due to the fact that the clients are

Hinted Handoff

2018-08-06 Thread Agrawal, Pratik
Hello all, We use Cassandra in non-conventional way, where our data is short termed (life cycle of about 20-30 minutes) where each record is updated ~5 times and then deleted. We have GC grace of 15 minutes. We are seeing 2 problems 1.) A certain number of Cassandra nodes goes down and then