Partition size estimation formula in 3.0

Hello, Until 3.0, we had a nice formula to estimate partition size : sizeof(partition keys) + sizeof(static columns) + countof(rows) * sizeof(regular columns) + countof(rows) * countof(regular columns) * sizeof(clustering columns) + 8 * count(values in partition) With the

Re: How Fast Does Information Spread With Gossip?

On Wed, Sep 14, 2016 at 1:49 PM, jerome wrote: > I was curious if anyone had any kind of statistics or ballpark figures on > how long it takes information to propagate through a cluster with Gossip? > I'm particularly interested in how fast information about the

Re: Nodetool repair

Hi Lokesh, Repair is a regular, very common and yet non trivial operations in Cassandra. A lot of people are struggling with it. Some good talks were done about repairs during the summit, you might want to have a look in the Datastax youtube channel in a few days :-).

Re: A question to sstable2json

Hi, Have you solved this issue? Sorry we did not answered you earlier. Is it a bug of Cassandra 2.1.11 Not that I am aware of. or I misused this command? What does your command look like? I could try it locally if that helps. C*heers, --- Alain Rodriguez - @arodream -

Re: High load on few nodes in a DC.

I was able to see most used partitions but the nodes with less load are serving more read and write requests for that particular partitions when compared to nodes with high load, how can i find if these nodes are serving as co-coordinators for those read and write requests ?? how can i find the

Re: High load on few nodes in a DC.

Hai Jeff, Thank, we are using RF 3 and cassandra version 2.1.8. Thanks Pranay. On Mon, Sep 19, 2016 at 10:55 AM, Jeff Jirsa wrote: > Is your replication_factor 2? Or is it 3? What version are you using? > > > > The most likely answer is some individual partition

Re: Question about replica and replication factor

Each individual read (where a read is a single row or single partition) will read from one node (ignoring read repairs) as each partition will be contained entirely on a single node. To read the full set of data, reads would hit at least two nodes (in practice, reads would likely end up being

Question about replica and replication factor

Hi there, I have a question about the replica and replication factor. For example, I have a cluster of 6 nodes in the same data center. Replication factor RF is set to 3 and the consistency level is default 1. According to this calculator http://www.ecyrd.com/cassandracalculator/,

RE: Export/Importing keyspace from a different sized cluster

I put together a shell wrapper around nodetool/sstableloader that I’ve been running for the past few years – https://github.com/AppliedInfrastructure/cassandra-snapshot-tools Always seemed to work well for these kinds of scenarios… Never really had to think about where SSTables were on the

RE: Question about replica and replication factor

Hi Ben, Thanks for the quick response. It's clear about the example for single row/partition. However, normally data are not single row. Then for this case, I'm still confused. http://docs.datastax.com/en/cassandra/2.1/cassandra/dml/architectureClientRequestsRead_c.html The link

Re: Question about replica and replication factor

Yes, I think for my case, at least two nodes need to be contacted to get the full set of data. But another thing comes up about dynamic snitch. It's the wrapped snitch and enabled by default and it'll choose the fastest/closest node to read data from. Another post is about this.

Re: Question about replica and replication factor

“replica” here means “a node that has a copy of the data for a given partition”. The scenario being discussed hear is CL > 1. In this case, rather than using up network and processing capacity sending all the data from all the nodes required to meet the consistency level, Cassandra gets the full

Re: Upgrade cassandra 2.1.14 to 3.0.7

> If you do not feel ready for incremental repairs, just adding the '-full' option to your 'nodetool repair' command should be enough to continue repairing as you currently are once using 3.0.7. This is not entirely true on 2.2+ after CASSANDRA-7586, since anti-compaction is always executed after

High load on few nodes in a DC.

when our cluster was under load i am seeing 1 or 2 nodes are on more load consistently when compared to others in dc i am not seeing any GC pauses or wide partitions is this can be those nodes are continuously serving as coordinators ?? how can i find what is the reason for high load on those

Re: Inconsistent results with Quorum at different times

Hi Jaydeep. > Now when I read using quorum then sometimes it returns data D1 and > sometimes it returns empty results. After tracing I found that when N1 and > N2 are chosen then we get empty data, when (N1/N2) and N3 are chosen then > D1 data is returned. This is an acceptable situation (ie.

Re: Upgrade cassandra 2.1.14 to 3.0.7

Hi Jean, Our concern is the repair, in 3.0.7 repairs inc are by default. Then it > means that once we do the upgrade to 3.0.7 we must follow the migration > process of repairs inc for all our data in order to mark the sstables as > repaired ? If you do not feel ready for incremental repairs,

Re: High load on few nodes in a DC.

Is your replication_factor 2? Or is it 3?  What version are you using? The most likely answer is some individual partition that’s either being written/read more than others, or is somehow impacting the cluster (wide rows are a natural candidate). You don’t mention your version, but most

Re: How many vnodes should I use for each node in my cluster?

Thanks for the input. I just kicked off another repair for one keyspace. Per the log, there are 1536 ranges to repair through. This makes sense: there are 6 nodes in the cluster, each having 256 token ranges, so 6*256 = 1536. So far, it is averaging 1 range per minute. So repair the keyspace will

Problems with schema creation

I have an automated tool we created which will create a keyspace, its tables, and add indexes in solr. But when I run the tool even for a new keyspace I end up getting ghost tables with the name “”. If I look in system_schema.tables I see a bunch of tables all named

Export/Importing keyspace from a different sized cluster

Hello, Assuming I can't get ports opened from source to target cluster to run sstableloader, what methods can I use to load a single keyspace from one cluster to another cluster of different size? Appreciate the help... Thanks, Justin

Re: large system hint partition

The reason for large partitions is that the partition key is just the uuid of the target node More recent (I think 2.2) don't have this problem since they write hints to the file system as per the commit log Sadly the large partitions make things worse when you are hinting hence presumably

Re: Nodetool repair

Hi Lokesh, Which version of Cassandra are you using? Which compaction strategy are you using? AFAIK, a repair doesn't trigger a major compaction, but I might be wrong here. What you could do is to run a repair for a subset of the ring (see `-st` and `-et` `nodetool repair` parameters). If you

Re: Export/Importing keyspace from a different sized cluster

You can ship the sstables to the destination (or any other server with Cassandra binary tools installed) via ssh/rsync and run sstableloader on the destination cluster as well. From: Justin Sanciangco Reply-To: "user@cassandra.apache.org"

Re: Export/Importing keyspace from a different sized cluster

CQLSH COPY FROM / COPY TO? There are some significant performance improvements in recent versions: https://issues.apache.org/jira/browse/CASSANDRA-11053 On Tue, 20 Sep 2016 at 07:49 Justin Sanciangco wrote: > Hello, > > > > Assuming I can’t get ports opened from source

Re: Problems with schema creation

Hi Josh, I too have had this issue on several clusters I manage, particularly when making schema changes. The worst part is, those nodes don't restart, and the tables can't be dropped. Basically you have to rebuild your whole cluster which often takes down time. Others have seen this on 3.0.x and

How does Local quorum consistency work ?? response from fastest node?

i always have this doubt when a cassandra node got a read request for local quorum consistency does coordinator node asks all nodes with replicas in that DC for response or just the fastest responding nodes to it who's count satisfy the local quorum. In this case RF is 3 Cassandra timeout during

Re: How does Local quorum consistency work ?? response from fastest node?

Hi Pranay, I'll try to answer the more precisely as I can. Note that what I'm going to explain is valid only for reads, write requests work differently. I'm assuming you have only one DC. 1. The coordinator gets a list of sorted live replicas. Replicas are sorted by proximity. (I'm not

RE: Export/Importing keyspace from a different sized cluster

So if I rsync the the sstables say from source node 1 and source node 2 to target node 1. Would I just run the command like this? From target host sstableloader -d From: Jeff Jirsa [mailto:jeff.ji...@crowdstrike.com] Sent: Monday, September 19, 2016 4:45 PM To: user@cassandra.apache.org

Re: Export/Importing keyspace from a different sized cluster

Something like that, depending on your version (which you didn’t specify). Note, though, that sstableloader is notoriously picky about the path to sstables. In particular, it really really really wants a directory structure that matches the directory structure on disk, and wants you to be at

RE: Export/Importing keyspace from a different sized cluster

I am running cqlsh 5.0.1 | Cassandra 2.1.11.969 | DSE 4.8.3 | CQL spec 3.2.1 | Doing the below command seemed to work sstableloader -d Thanks for the help! From: Jeff Jirsa [mailto:jeff.ji...@crowdstrike.com] Sent: Monday, September 19, 2016 5:49 PM To: user@cassandra.apache.org Subject: