Re: C* throws OOM error despite use of automatic paging

There are no tombstones. Mohammed On Jan 12, 2015, at 9:11 PM, Dominic Letz mailto:dominicl...@exosite.com>> wrote: Does your use case include many tombstones? If yes then that might explain the OOM situation. If you want to know for sure you can enable the heap dump generation on crash in

Re: C* throws OOM error despite use of automatic paging

Does your use case include many tombstones? If yes then that might explain the OOM situation. If you want to know for sure you can enable the heap dump generation on crash in cassandra-env.sh just uncomment JVM_OPTS="$JVM_OPTS -XX:+HeapDumpOnOutOfMemoryError" and then run your query again. The hea

nodetool compact cannot remove tombstone in system keyspace

Hi, When I connect to C* with driver, I found some warnings in the log (I increased tombstone_failure_threshold to 15 to see the warning) WARN [ReadStage:5] 2015-01-13 12:21:14,595 SliceQueryFilter.java (line 225) Read 34188 live and 104186 tombstoned cells in system.schema_columns (see

problem in exporting large table

Hi All, We are using C* 2.1. we need to export data of one table (consist 10 lacs records) using COPY command. After executing copy command cqlsh hangs and get stuck . Please help in resolving the same or provide any alternative for the same. pfb table stats: Keyspace: clickstream Read Co

RE: C* throws OOM error despite use of automatic paging

The heap usage is pretty low ( less than 700MB) when the application starts. I can see the heap usage gradually climbing once the application starts. C* does not log any errors before OOM happens. Data is on EBS. Write throughput is quite high with two applications simultaneously pumping data i

Re: How do you apply (CQL) schema modification patches across a cluster?

Are you changing schema so frequently that you really need to automate this process? I guess not. Though, if such a (consistent) process existed, I'd love to use it.  The single node solution will have to do. Because of the source code change, it seems I still have to make sure that the patch sc

Re: How do you apply (CQL) schema modification patches across a cluster?

On Mon, Jan 12, 2015 at 5:46 PM, Sotirios Delimanolis wrote: > So do we have to guarantee that the schema change will be backwards > compatible? Which node should send the schema change query? Should we just > make all nodes send it and ignore failures? > - "Yes" is the easiest answer. - Any sin

How do you apply (CQL) schema modification patches across a cluster?

Hey all, Assuming a cluster with X > 1 application nodes backed by Y > 1 Cassandra nodes, how do you best apply a schema modification? Typically, such a schema modification is going to be done in parallel with code changes (for querying the table) so all application nodes have to be restarted.

Design a system maintaining historical view of users.

Hey Guys, I am seeking advice on design a system that maintains a historical view of a user's activities in past one year. Each user can have different activities: email_open, email_click, item_view, add_to_cart, purchase etc. The query I would like to do is, for example, Find all customers who br

Re: C* throws OOM error despite use of automatic paging

I think it's more accurate that to say that auto paging prevents one type of OOM. It's premature to diagnose it as 'not happening'. What is heap usage when you start? Are you storing your data on EBS? What kind of write throughput do you have going on at the same time? What errors do you have in t

Re: Permanent ReadTimeout

To precise your remarks: 1) About 30 sec GC. I know that after time my cluster had such problem, we added "magic" flag, but result will be in ~2 weeks (as I presented in screen on StackOverflow). If you have any idea how can fix/diagnose this problem, I will be very grateful. 2) It is probably tr

Re: error on using sstable loader

On Mon, Jan 12, 2015 at 4:26 AM, Rahul Bhardwaj < rahul.bhard...@indiamart.com> wrote: > sstableloader -d 162.217.99.217 > /var/lib/cassandra/data/clickstream/business_feed_new > ERROR 17:50:48,218 Unable to initialize MemoryMeter (jamm not specified as > javaagent). This means Cassandra will be

Re: Datastax Cassandra Java Driver executeAsynch question.

Hi Bogdan, This question would be better on the specific driver's mailing list. Assuming you are using the Java driver the mailing list is [1]. As for your question look into PoolingOptions [2] that you pass when configuring the Cluster instance. [1]: https://groups.google.com/a/lists.datastax.co

Re: Permanent ReadTimeout

If you're getting 30 second GC's, this all by itself could and probably does explain the problem. If you're writing exclusively to A, and there are frequent partitions between A and B, then A is potentially working a lot harder than B, because it needs to keep track of hinted handoffs to replay to

Cassandra - Meetup Group - Monday 1/26 - Choice Hotels - Phoenix, Arizona

Hi All! We are hosting a Cassandra Meetup Group at our office in Phoenix, AZ on Monday (1/26). If anyone is in the Phoenix area and would like to attend please let me know or RSVP through the Cassandra Meetup page. Here is t

Datastax Cassandra Java Driver executeAsynch question.

Hello all, In my implementation of the FutureCallBack<> interface in the onSuccess method, I put Thread.currentThread.getName(). What I saw was that there is a ThreadPool... That is all fine, but seems to me that the pool does not have that many threads. About 10 from my observations - I did no

Re: Startup failure (Core dump) in Solaris 11 + JDK 1.8.0

Probably a bad answers but I was able to run on 1.7 jdk .So if possible can downsize you jdk version and try. I hit the block on RedHat enterprise... On Jan 12, 2015 9:31 PM, "Bernardino Mota" wrote: > Hi all, > > I'm trying to install Cassandra 2.1.2 in Solaris 11 but I'm getting a core > dump

Startup failure (Core dump) in Solaris 11 + JDK 1.8.0

Hi all, I'm trying to install Cassandra 2.1.2 in Solaris 11 but I'm getting a core dump at startup. Any help is appreciated, since I can't change the operating system... *My setup is:* - Solaris 11 - JDK build 1.8.0_25-b17 *The error:* appserver02:/opt/apache-cassandra-2.1.2/bin$ ./cassand

Permanent ReadTimeout

*Environment* - Cassandra 2.1.0 - 5 nodes in one DC (DC_A), 4 nodes in second DC (DC_B) - 2500 writes per seconds, I write only to DC_A with local_quorum - minimal reads (usually none, sometimes few) *Problem* After a few weeks of running I cannot read any data from my cluster, beca

Re: setting up prod cluster

I might be misinterpreting you, but it seems you are only using one seed per node. Is there a specific reason for that? A node can have multiple seeds in its seed list. It is my understanding that typically, every node in a cluster has the same seed list. On Sun, Jan 11, 2015 at 10:03 PM, Tim Dunp

Re: setting up prod cluster

Hi Tim, replies inline below. On Sun, Jan 11, 2015 at 8:03 PM, Tim Dunphy wrote: > Hey all, > > I've been experimenting with Cassandra on a small scale and in my own > sandbox for a while now. I'm pretty used to working with it to get small > clusters up and running and gossiping with each othe

Re: Growing SSTable count as Cassandra does not saturate the disk I/O

Are you using compression on the sstables? If so, possibly you're CPU bound instead of disk bound. On Mon, Jan 12, 2015 at 3:47 AM, William Saar wrote: > Hi, > > We are running a test with Cassandra 2.1.2 on Fusion I/O drives where we > load about 2 billion rows of data during a few hours each

Re: High read latency after data volume increased

There's likely 2 things occurring 1) the cfhistograms error is due to https://issues.apache.org/jira/browse/CASSANDRA-8028 Which is resolved in 2.1.3. Looks like voting is under way for 2.1.3. As rcoli mentioned, you are running the latest open source of C* which should be treated as beta until a

error on using sstable loader

Hi All, While using bulk loader we are getting this error: sstableloader -d 162.217.99.217 /var/lib/cassandra/data/clickstream/business_feed_new ERROR 17:50:48,218 Unable to initialize MemoryMeter (jamm not specified as javaagent). This means Cassandra will be unable to measure object sizes ac

Growing SSTable count as Cassandra does not saturate the disk I/O

Hi, We are running a test with Cassandra 2.1.2 on Fusion I/O drives where we load about 2 billion rows of data during a few hours each night onto a 6-node cluster, but compactions that run 24/7 don't seem to be keeping up as the number of SSTables keep growing and our disks seem way underutilize

Re: how dump a query result into csv file

sry consider these stats: nodetool cfstats clickstream.business_feed_new Keyspace: clickstream Read Count: 2108 Read Latency: 8.148092030360532 ms. Write Count: 923452 Write Latency: 2.8382575358545976 ms. Pending Flushes: 0 Table: business_f

Re: how dump a query result into csv file

Hi, Thanks for your quick reply. But I know this command , but for one table which has around 10lacs rows, this command (Copy table_name to 'table_name.csv' ) get stuck for long time also slows down my cluster. pfb table stats: nodetool cfstats clickstream.business_feed Keyspace: clickstream

RE: how dump a query result into csv file

I think this might be what you are looking for http://www.datastax.com/documentation/cql/3.1/cql/cql_reference/copy_r.html Andi From: Rahul Bhardwaj [rahul.bhard...@indiamart.com] Sent: 12 January 2015 09:22 To: user Subject: how dump a query result into csv file

how dump a query result into csv file

Hi All, I want to dump a query result into a csv file with custom column delimiter. Please help. Regards: Rahul Bhardwaj -- Follow IndiaMART.com for latest updates on this and more: