Some things that are helpful:
- What version of Cassandra
- How much memory allocated to heap
- How much memory allocated to direct memory for the JVM
- How much memory on the full system
- Do you have a heap dump?
- Do you have a heap histogram?
- How much data on disk?
- What are your compression and bloom filter settings (both use off-heap
memory and scale with size of data on disk, but should not leak)
On Thu, Jun 18, 2020 at 7:29 AM Reid Pinchback
wrote:
> Just to confirm, is this memory decline outside of the Cassandra process?
> If so, I’d look at crond and at memory held for network traffic. Those are
> the two areas I’ve seen leak. If you’ve configured to have swap=0, then
> you end up in a position where even if the memory usage is stale, nothing
> can push the stale pages out of the way.
>
>
>
> *From: *Rahul Reddy
> *Reply-To: *"user@cassandra.apache.org"
> *Date: *Thursday, June 18, 2020 at 10:27 AM
> *To: *"user@cassandra.apache.org"
> *Subject: *Memory decline
>
>
>
> *Message from External Sender*
>
> Hello,
>
>
>
> Im seeing continuous decline in memory on a Cassandra instance used to
> have 20g free memory 15 days back and now its 15g and continue to go down.
> Same instance it caused the cassandra instance crash before. Can you please
> give me some pointers to look for which is causing continuous decline in
> memory
>