Re: Minimum System Requirements

I’ll add a few cautionary notes: * JVM object overhead has memory allocation efficiency issues possible with heap >= 32gig, but yes to the added memory for off-heap storage and O/S buffer cache. * C* creates a lot of threads, but the number active can sometimes be rather small. Dependin

Re: JMX mBean for gossipinfo/status

Thanks for explanation, this helps. On Mon, Mar 30, 2020 at 12:15 PM J.B. Langston wrote: > Each nodetool subcommand is defined here. > https://github.com/apache/cassandra/tree/trunk/src/java/org/apache/cassandra/tools/nodetool > > Each command will call back into the NodeProbe object (sometimes

Re: Minimum System Requirements

I recently had to set up an integration testing environment that involves running multiple C* instances in containers using docker-compose. I am able to do so with a total memory for the container set at 512 MB and a 256 MB heap for C*. This is with C* 3.11.4. Going below 512 MB causes the containe

Re: JMX mBean for gossipinfo/status

Each nodetool subcommand is defined here. https://github.com/apache/cassandra/tree/trunk/src/java/org/apache/cassandra/tools/nodetool Each command will call back into the NodeProbe object (sometimes indirectly), which makes the actual JMX calls: https://github.com/apache/cassandra/blob/trunk/src/j

Re: JMX mBean for gossipinfo/status

I tried looking at the org.apache.cassandra.db:type=StorageService mBean, but don't see an option for the datacenter On Mon, Mar 30, 2020 at 11:55 AM Jai Bheemsen Rao Dhanwada < jaibheem...@gmail.com> wrote: > Hello All, > > I am trying to find the mBean that gives information for "node tool > go

JMX mBean for gossipinfo/status

Hello All, I am trying to find the mBean that gives information for "node tool gossipinfo" or "nodetool status". Back ground: I am trying find the available Datacenters in my Cassandra cluster using the JMX mBeans. Thanks in advance.

Re: High value of "All Time Blocked" for "Native-Transport-Requests"

To add on to my previous email, I think we get this error when actual off heap memory breaches "off heap memory limit" as mentioned in this JIRA . On Mon, Mar 30, 2020 at 3:10 PM manish khandelwal < manishkhandelwa...@gmail.com> wrote: > I ha

Re: High value of "All Time Blocked" for "Native-Transport-Requests"

I have already updated that property to mmap_index_only. And in pmap I could see only index files are loaded into memory not the SSTables. I feel this is some to do with direct memory buffer. There is a opened JIRA ticket https://issues.apache.org/jira/browse/CASSANDRA-10930 as well regarding this.

Re: High value of "All Time Blocked" for "Native-Transport-Requests"

> > 1. Why Cassandra memory usage remains high even if no traffic is run? > 2. In which case I will get above error ( *java.lang.OutOfMemoryError: > Direct buffer memory*). How to avoid those cases? > I don't have enough information to know if it applies to your case but there's a good possibility

Re: High value of "All Time Blocked" for "Native-Transport-Requests"

Thanks for the response. With continuous runs I am observing my off heap memory increasing and *memory usage remains high even if no traffic is running*. Sometimes a node is hung with following error: ERROR [ReadStage-5] 2020-03-12 20:47:46,406 JVMStabilityInspector.java:74 - OutOfMemory error let