This is the closest JIRA that comes to mind (from memory, I didn't search, there may be others): https://issues.apache.org/jira/browse/CASSANDRA-8150
The best blog that's all in one place on tuning GC in cassandra is actually Amy's 2.1 tuning guide: https://tobert.github.io/pages/als-cassandra-21-tuning-guide.html - it's somewhat out of date as it's for 2.1, but since that's what you're running, that works out in your favor. On Thu, Aug 30, 2018 at 10:53 AM Jai Bheemsen Rao Dhanwada < jaibheem...@gmail.com> wrote: > Hi Jeff, > > Is there any JIRA that talks about increasing the HEAP will help? > Also, any other alternatives than increasing the HEAP Size? last time when > I tried increasing the heap, longer GC Pauses caused more damage in terms > of latencies while gc pause. > > On Wed, Aug 29, 2018 at 11:07 PM Jai Bheemsen Rao Dhanwada < > jaibheem...@gmail.com> wrote: > >> okay, thank you >> >> On Wed, Aug 29, 2018 at 11:04 PM Jeff Jirsa <jji...@gmail.com> wrote: >> >>> You’re seeing an OOM, not a socket error / timeout. >>> >>> -- >>> Jeff Jirsa >>> >>> >>> On Aug 29, 2018, at 10:56 PM, Jai Bheemsen Rao Dhanwada < >>> jaibheem...@gmail.com> wrote: >>> >>> Jeff, >>> >>> any idea if this is somehow related to : >>> https://issues.apache.org/jira/browse/CASSANDRA-11840? >>> does increasing the value of streaming_socket_timeout_in_ms to a higher >>> value helps? >>> >>> On Wed, Aug 29, 2018 at 10:52 PM Jai Bheemsen Rao Dhanwada < >>> jaibheem...@gmail.com> wrote: >>> >>>> I have 72 nodes in the cluster, across 8 datacenters.. the moment I try >>>> to increase the node above 84 or so, the issue starts. >>>> >>>> I am still using CMS Heap, assuming it will create more harm if I >>>> increase the heap size beyond 8G(recommended). >>>> >>>> On Wed, Aug 29, 2018 at 6:53 PM Jeff Jirsa <jji...@gmail.com> wrote: >>>> >>>>> Given the size of your schema, you’re probably getting flooded with a >>>>> bunch of huge schema mutations as it hops into gossip and tries to pull >>>>> the >>>>> schema from every host it sees. You say 8 DCs but you don’t say how many >>>>> nodes - I’m guessing it’s a lot? >>>>> >>>>> This is something that’s incrementally better in 3.0, but a real >>>>> proper fix has been talked about a few times - >>>>> https://issues.apache.org/jira/browse/CASSANDRA-11748 and >>>>> https://issues.apache.org/jira/browse/CASSANDRA-13569 for example >>>>> >>>>> In the short term, you may be able to work around this by increasing >>>>> your heap size. If that doesn’t work, there’s an ugly ugly hack that’ll >>>>> work on 2.1: limiting the number of schema blobs you can get at a time - >>>>> in this case, that means firewall off all but a few nodes in your cluster >>>>> for 10-30 seconds, make sure it gets the schema (watch the logs or file >>>>> system for the tables to be created), then remove the firewall so it can >>>>> start the bootstrap process (it needs the schema to setup the streaming >>>>> plan, and it needs all the hosts up in gossip to stream successfully, so >>>>> this is an ugly hack to give you time to get the schema and then heal the >>>>> cluster so it can bootstrap). >>>>> >>>>> Yea that’s awful. Hopefully either of the two above JIRAs lands to >>>>> make this less awful. >>>>> >>>>> >>>>> >>>>> -- >>>>> Jeff Jirsa >>>>> >>>>> >>>>> On Aug 29, 2018, at 6:29 PM, Jai Bheemsen Rao Dhanwada < >>>>> jaibheem...@gmail.com> wrote: >>>>> >>>>> It fails before bootstrap >>>>> >>>>> streaming throughpu on the nodes is set to 400Mb/ps >>>>> >>>>> On Wednesday, August 29, 2018, Jeff Jirsa <jji...@gmail.com> wrote: >>>>> >>>>>> Is the bootstrap plan succeeding (does streaming start or does it >>>>>> crash before it logs messages about streaming starting)? >>>>>> >>>>>> Have you capped the stream throughput on the existing hosts? >>>>>> >>>>>> -- >>>>>> Jeff Jirsa >>>>>> >>>>>> >>>>>> On Aug 29, 2018, at 5:02 PM, Jai Bheemsen Rao Dhanwada < >>>>>> jaibheem...@gmail.com> wrote: >>>>>> >>>>>> Hello All, >>>>>> >>>>>> We are seeing some issue when we add more nodes to the cluster, where >>>>>> new node bootstrap is not able to stream the entire metadata and fails to >>>>>> bootstrap. Finally the process dies with OOM (java.lang.OutOfMemoryError: >>>>>> Java heap space) >>>>>> >>>>>> But if I remove few nodes from the cluster we don't see this issue. >>>>>> >>>>>> Cassandra Version: 2.1.16 >>>>>> # of KS and CF : 100, 3000 (approx) >>>>>> # of DC: 8 >>>>>> # of Vnodes per node: 256 >>>>>> >>>>>> Not sure what is causing this behavior, has any one come across this >>>>>> scenario? >>>>>> thanks in advance. >>>>>> >>>>>>
