Strange Garbage Collections results in service impact

Hello Cassandra community, I am new in the list, so no experience in posting questions. We have Cassandra deployed in our product. In one of the production nodes I see the following. The Cassandra nodes belonging to a specific datacenter have frequent Garbage collection impacting the system

RE: Strange Garbage Collections results in service impact

info from the Cassandra nodes affected seems to be >related with the root cause of the problem. Does this ring a bell? Have anyone observed such behavior before? What could have caused it? Could it be something in the JVM? BR MK From: Michail Kotsiouros via user Sent: Friday, July 1, 2022 11

Log messages "MUTATION messages were dropped" in system.log

Hello Cassandra community, I see the following log lines in the Cassandra nodes of 2 datacenters that participate in a cluster of 6 datacenters. INFO [ScheduledTasks:1] 2022-09-12 17:19:44,422 MessagingService.java:1236 - MUTATION messages were dropped in last 5000 ms: 0 internal and 2 cross

Cassandra GC tuning

Hello community, I observe some GC pauses while trying to create snapshots of a keyspace. The GC pauses as such are not long, even though they are reported in logs. The problem is the CPU utilization which affects other applications deployed in my server. Do you have any articles or

RE: Cassandra GC tuning

or IO scheduler tuning. There's a patch somewhere to throttle hardlinks to try to mitigate this. On Mon, Sep 19, 2022 at 3:45 AM Michail Kotsiouros via user mailto:user@cassandra.apache.org>> wrote: Hello community, I observe some GC pauses while trying to create snapshots of a keys

RE: Log messages "MUTATION messages were dropped" in system.log

Kotsiouros via user Sent: Tuesday, September 27, 2022 17:36 To: user@cassandra.apache.org Subject: Log messages "MUTATION messages were dropped" in system.log Hello Cassandra community, I see the following log lines in the Cassandra nodes of 2 datacenters that participate in a cl

RE: Cassandra GC tuning

sandra-21-tuning-guide.html> [favicon.ico]<https://tobert.github.io/pages/als-cassandra-21-tuning-guide.html> On Sep 20, 2022, at 5:27 AM, Michail Kotsiouros via user mailto:user@cassandra.apache.org>> wrote:  Hello community, BTW I am using Cassandra 3.11.4. From your comments

Questions about high read latency and related metrics

Hello Cassandra community, I see the following metrics in JMX Metric Name org.apache.cassandra.metrics.Table... MinPartitionSize Gauge Size of the smallest compacted partition (in bytes). MaxPartitionSize Gauge Size of the largest compacted partition (in bytes). MeanPartitionSize Gauge Size

RE: Questions about high read latency and related metrics

Hello Erick, Thanks a lot for the immediate reply but still the difference between those 2 metrics is not clear to me. BR MK From: Erick Ramirez Sent: Thursday, May 11, 2023 13:04 To: user@cassandra.apache.org Subject: Re: Questions about high read latency and related metrics The min/max/mean

RE: Questions about high read latency and related metrics

Hello Erick, No Max/Min/Mean vs Histogram difference is clear. What confuses me is the description of those metrics: Size of the compacted partition (in bytes). Vs estimated partition size. I am after what is measured by each metric. To be more specific: What metric should be consider when we

RE: Questions about high read latency and related metrics

topic. BR MK From: Michail Kotsiouros via user Sent: Thursday, May 11, 2023 14:08 To: user@cassandra.apache.org Subject: RE: Questions about high read latency and related metrics Hello Erick, No Max/Min/Mean vs Histogram difference is clear. What confuses me is the description of those metrics