Re: node decommission
No, decommission does not decrease the load, as it only streams the data to other nodes, but doesn't remove them locally. However, decommission also shouldn't increase the load either. I can't offer an explanation for the load increase in your case. On 26/09/2022 15:03, Marc Hoppins wrote: Hulloa all, I started a decommission. Node load was 1.08TiB. After 6 or so hours the load is at 1.12TiB. Shouldn't it be DECREASING?
node decommission
Hulloa all, I started a decommission. Node load was 1.08TiB. After 6 or so hours the load is at 1.12TiB. Shouldn't it be DECREASING?
Re: Cassandra data sync time
It looks like you have replication factor of 3 and total data size of 1.43 GB per node. That's very small amount of data. Assuming the bottleneck is the network, not CPU or disk, and your 50 Mbps bandwidth is between each pair of servers across the two DCs (i.e. not the total bandwidth available between the DCs), the streaming process itself should only take minutes. On 26/09/2022 12:14, Kaushal Shriyan wrote: On Fri, Sep 23, 2022 at 8:39 PM Bowen Song via user wrote: What's your definition of "sync"? Streaming all the existing data to the new DC? or the time lag between a write request is completed in one DC and the other DC? The former can be estimated based on a few facts about your setup (number of nodes, data size, etc.) and some measured data (streaming speed). The latter is usually just slightly above the network latency, but can spike up if and when the network between DCs suffer from temporary connectivity issues. Hi Bowen, Thanks for the quick response. I was referring to streaming all the existing data to the new DC(DC2). We have On 23/09/2022 15:58, Kaushal Shriyan wrote: Hi, Is there a way to measure cassandra nodes data sync time between DC1 and DC2? Currently DC1 is the prod datacenter. I am adding DC2 to the new data center by referring to https://docs.apigee.com/private-cloud/v4.51.00/adding-data-center?hl=en. https://docs.apigee.com/release/supported-software Cassandra version :- 2.1.22 Is there a way to measure the time taken to sync the data in current prod DC1 (Cassandra Node 1, 2 ,3) and the new DC2 (Cassandra Node 4, 5 ,6)? Thanks in advance. Best Regards, Kaushal Hi Bowen, Thanks for the quick response. Streaming all the existing data from the current prod DC1 (Cassandra Node 1, 2 ,3) to the new DC2 (Cassandra Node 4, 5 ,6). Data bandwidth between DC1 and DC2 is around 50 Mbps. Please let me know if you need any additional details. Thanks in advance. /opt/apigee/apigee-cassandra/bin/nodetool status Datacenter: dc-1 Status=Up/Down |/ State=Normal/Leaving/Joining/Moving -- Address Load Tokens Owns (effective) Host ID Rack UN 192.198.11.4 1.43 GB 1 100.0% dbfbd44f-kec5-4f91-bc7d-c31582aec35a ra-1 UN 192.198.11.128 1.43 GB 1 100.0% bc55019c-8ccb-4403-9dc4-481b90a262f6 ra-1 UN 192.198.11.3 1.43 GB 1 100.0% 4402901c-4562-4f0f-b14a-4eed40a9836c ra-1 _On Node1_ du -ch /opt/apigee/data/apigee-cassandra/data 1.7G total _On Node2 _ du -ch /opt/apigee/data/apigee-cassandra/data _On Node3 _ du -ch /opt/apigee/data/apigee-cassandra/data Best Regards, Kaushal
Re: Cassandra java > 15
Correction -- It has been brought to my attention that there are no plans for 5.0 yet so Java 17 support might be added sooner in the next 4.x release if it's ready. Cheers! > There is no support for Java 17 yet. The plan is to add it in Cassandra > 5.0 [1]. > > [1] https://issues.apache.org/jira/browse/CASSANDRA-16895 >
Re: Cassandra data sync time
On Fri, Sep 23, 2022 at 8:39 PM Bowen Song via user < user@cassandra.apache.org> wrote: > What's your definition of "sync"? Streaming all the existing data to the > new DC? or the time lag between a write request is completed in one DC and > the other DC? > > The former can be estimated based on a few facts about your setup (number > of nodes, data size, etc.) and some measured data (streaming speed). > > The latter is usually just slightly above the network latency, but can > spike up if and when the network between DCs suffer from temporary > connectivity issues. > Hi Bowen, Thanks for the quick response. I was referring to streaming all the existing data to the new DC(DC2). We have > On 23/09/2022 15:58, Kaushal Shriyan wrote: > > Hi, > > Is there a way to measure cassandra nodes data sync time between DC1 and > DC2? Currently DC1 is the prod datacenter. I am adding DC2 to the new data > center by referring to > https://docs.apigee.com/private-cloud/v4.51.00/adding-data-center?hl=en. > > https://docs.apigee.com/release/supported-software > Cassandra version :- 2.1.22 > > Is there a way to measure the time taken to sync the data in current prod > DC1 (Cassandra Node 1, 2 ,3) and the new DC2 (Cassandra Node 4, 5 ,6)? > > Thanks in advance. > > Best Regards, > > Kaushal > > Hi Bowen, Thanks for the quick response. Streaming all the existing data from the current prod DC1 (Cassandra Node 1, 2 ,3) to the new DC2 (Cassandra Node 4, 5 ,6). Data bandwidth between DC1 and DC2 is around 50 Mbps. Please let me know if you need any additional details. Thanks in advance. /opt/apigee/apigee-cassandra/bin/nodetool status Datacenter: dc-1 Status=Up/Down |/ State=Normal/Leaving/Joining/Moving -- AddressLoad Tokens Owns (effective) Host ID Rack UN 192.198.11.41.43 GB1 100.0% dbfbd44f-kec5-4f91-bc7d-c31582aec35a ra-1 UN 192.198.11.128 1.43 GB1 100.0% bc55019c-8ccb-4403-9dc4-481b90a262f6 ra-1 UN 192.198.11.31.43 GB1 100.0% 4402901c-4562-4f0f-b14a-4eed40a9836c ra-1 *On Node1* du -ch /opt/apigee/data/apigee-cassandra/data 1.7G total *On Node2* du -ch /opt/apigee/data/apigee-cassandra/data *On Node3* du -ch /opt/apigee/data/apigee-cassandra/data Best Regards, Kaushal
Re: Cassandra java > 15
There is no support for Java 17 yet. The plan is to add it in Cassandra 5.0 [1]. By default, builds are done with Java 8. You can build with Java 11 by setting the flags documented on the site [2]. Cheers! [1] https://issues.apache.org/jira/browse/CASSANDRA-16895 [2] https://cassandra.apache.org/_/development/ide.html
