Re: Regarding SSTableSplit Utility
On Fri, Feb 6, 2015 at 1:15 AM, Parth Setya setya.pa...@gmail.com wrote: SSTable split gives the following error *Exception in thread main java.lang.OutOfMemoryError: GC overhead limit exceede d * How much heap is available to the JVM sstablesplit is running in? Increase it. *Cassandra Version: 2.0.3* This version has serious known bugs, update to the most recent 2.0.x version ASAP. Also does sstablesplit internally invoke compaction? The source code is available... :D As a safety note, please be sure to run sstablesplit either outside of the data directory or with the cassandra node stopped. =Rob
Re: Mutable primary key in a table
On Fri, Feb 6, 2015 at 7:43 PM, Adil adil.cha...@gmail.com wrote: Hi, it seems you are doing some thing wrong in your model, why can you go with updating columns of key1 instead of deleting/inserting row key? You can't update a primary key column with update statements.
Regarding SSTableSplit Utility
Hello people SSTable split gives the following error *Exception in thread main java.lang.OutOfMemoryError: GC overhead limit exceede d at com.googlecode.concurrentlinkedhashmap.ConcurrentLinkedHashMap.drainB uffers(ConcurrentLinkedHashMap.java:434) at com.googlecode.concurrentlinkedhashmap.ConcurrentLinkedHashMap.tryToD rainBuffers(ConcurrentLinkedHashMap.java:412) at com.googlecode.concurrentlinkedhashmap.ConcurrentLinkedHashMap.afterC ompletion(ConcurrentLinkedHashMap.java:344) at com.googlecode.concurrentlinkedhashmap.ConcurrentLinkedHashMap.put(Co ncurrentLinkedHashMap.java:771) at com.googlecode.concurrentlinkedhashmap.ConcurrentLinkedHashMap.put(Co ncurrentLinkedHashMap.java:743) at org.apache.cassandra.cache.ConcurrentLinkedHashCache.put(ConcurrentLi nkedHashCache.java:101) at org.apache.cassandra.cache.ConcurrentLinkedHashCache.put(ConcurrentLi nkedHashCache.java:27) at org.apache.cassandra.cache.InstrumentingCache.put(InstrumentingCache. java:44) at org.apache.cassandra.cache.AutoSavingCache.loadSaved(AutoSavingCache. java:130) at org.apache.cassandra.db.ColumnFamilyStore.init(ColumnFamilyStore.ja va:264) at org.apache.cassandra.db.ColumnFamilyStore.createColumnFamilyStore(Col umnFamilyStore.java:415) at org.apache.cassandra.db.ColumnFamilyStore.createColumnFamilyStore(Col umnFamilyStore.java:387) at org.apache.cassandra.db.Keyspace.initCf(Keyspace.java:314) at org.apache.cassandra.db.Keyspace.init(Keyspace.java:268) at org.apache.cassandra.db.Keyspace.open(Keyspace.java:110) at org.apache.cassandra.db.Keyspace.open(Keyspace.java:88) at org.apache.cassandra.service.StorageService.getLoad(StorageService.ja va:1899) at org.apache.cassandra.db.compaction.CompactionInfo$Holder.init(Compa ctionInfo.java:124) at org.apache.cassandra.db.compaction.AbstractCompactionIterable.init( AbstractCompactionIterable.java:40) at org.apache.cassandra.db.compaction.CompactionIterable.init(Compacti onIterable.java:42) at org.apache.cassandra.db.compaction.CompactionTask.runWith(CompactionT ask.java:126) at org.apache.cassandra.io.util.DiskAwareRunnable.runMayThrow(DiskAwareR unnable.java:48) at org.apache.cassandra.utils.WrappedRunnable.run(WrappedRunnable.java:2 8) at org.apache.cassandra.db.compaction.CompactionTask.executeInternal(Com pactionTask.java:60) at org.apache.cassandra.db.compaction.AbstractCompactionTask.execute(Abs tractCompactionTask.java:59) at org.apache.cassandra.db.compaction.SSTableSplitter.split(SSTableSplit ter.java:38) at org.apache.cassandra.tools.StandaloneSplitter.main(StandaloneSplitter .java:150) * *Cassandra Version: 2.0.3* *Size of sstable : 2 GB* *Note: I ran a major compaction before running this command.* How can I fix this? Also does sstablesplit internally invoke compaction? Best Parth
Re: Writing the same column frequently - anti pattern?
Hi, If the writes are coming from the same machine, you could potentially use request collapsing https://github.com/Netflix/Hystrix/wiki/How-To-Use#request-collapsing to avoid the duplicate writes. Just an idea, Jens On Fri, Feb 6, 2015 at 1:15 AM, Andreas Finke andreas.fi...@solvians.com wrote: Hi, we are currently writing the same column within a row multiple times (up to 10 times a second). I am familiar with the concept of tombstones in SSTables. My question is: I assume that in our case in most cases when a column gets overwritten it still resides in the memtable. So I assume for that particular case no tombstone is set but the column is replaced in memory and then the 'newest' version is flushed to disk. Is this assumption correct? Or Is writing the same column an an anti-pattern? I am thankful for any input. Regards Andi -- Jens Rantil Backend engineer Tink AB Email: jens.ran...@tink.se Phone: +46 708 84 18 32 Web: www.tink.se Facebook https://www.facebook.com/#!/tink.se Linkedin http://www.linkedin.com/company/2735919?trk=vsrp_companies_res_phototrkInfo=VSRPsearchId%3A1057023381369207406670%2CVSRPtargetId%3A2735919%2CVSRPcmpt%3Aprimary Twitter https://twitter.com/tink
how to batch the select query to reduce network communication
create table t {
a int,
b int,
c int
}
if i want to execute
select * from t where a = 1 and b = 2 limit 10;
select * from t where a = 1 and b = 3 limit 10;
how can i batch this, and only execute once to get the result
Mutable primary key in a table
Hi guys, I want to take a row with primary key K1, rewrite it with primary key K2, and delete the original data with key K1, atomically. It seems like the only solution which won't have race conditions is to use batch statement to delete the old row and insert the new one. But the documentation of batch operation makes me nervous. The specific parts in docs are the ones which say that all nodes in your cluster become stressed if you use logged batches(default one). Is it a solved problem already? Cheers, Ajaya
Re: Mutable primary key in a table
Hi, it seems you are doing some thing wrong in your model, why can you go with updating columns of key1 instead of deleting/inserting row key? 2015-02-06 15:02 GMT+01:00 Ajaya Agrawal ajku@gmail.com: Hi guys, I want to take a row with primary key K1, rewrite it with primary key K2, and delete the original data with key K1, atomically. It seems like the only solution which won't have race conditions is to use batch statement to delete the old row and insert the new one. But the documentation of batch operation makes me nervous. The specific parts in docs are the ones which say that all nodes in your cluster become stressed if you use logged batches(default one). Is it a solved problem already? Cheers, Ajaya
Re: how to batch the select query to reduce network communication
Hi,
You can't. Batches are only available for INSERT, UPDATE and DELETE
operations. Batches exist to give Cassandra some atomicity, as in, or all
operations succeed or all fail.
Regards,
Regards,
Carlos Juzarte Rolo
Cassandra Consultant
Pythian - Love your data
rolo@pythian | Twitter: cjrolo | Linkedin: *linkedin.com/in/carlosjuzarterolo
http://linkedin.com/in/carlosjuzarterolo*
Tel: 1649
www.pythian.com
On Fri, Feb 6, 2015 at 12:21 PM, diwayou diwa...@vip.qq.com wrote:
create table t {
a int,
b int,
c int
}
if i want to execute
select * from t where a = 1 and b = 2 limit 10;
select * from t where a = 1 and b = 3 limit 10;
how can i batch this, and only execute once to get the result
--
--
Re: how to batch the select query to reduce network communication
As an alternative, you could always execute the async to Cassandra and then
iterate over the results as they come in.
Cheers,
Jens
On Fri, Feb 6, 2015 at 12:39 PM, Carlos Rolo r...@pythian.com wrote:
Hi,
You can't. Batches are only available for INSERT, UPDATE and DELETE
operations. Batches exist to give Cassandra some atomicity, as in, or all
operations succeed or all fail.
Regards,
Regards,
Carlos Juzarte Rolo
Cassandra Consultant
Pythian - Love your data
rolo@pythian | Twitter: cjrolo | Linkedin: *linkedin.com/in/carlosjuzarterolo
http://linkedin.com/in/carlosjuzarterolo*
Tel: 1649
www.pythian.com
On Fri, Feb 6, 2015 at 12:21 PM, diwayou diwa...@vip.qq.com wrote:
create table t {
a int,
b int,
c int
}
if i want to execute
select * from t where a = 1 and b = 2 limit 10;
select * from t where a = 1 and b = 3 limit 10;
how can i batch this, and only execute once to get the result
--
--
Jens Rantil
Backend engineer
Tink AB
Email: jens.ran...@tink.se
Phone: +46 708 84 18 32
Web: www.tink.se
Facebook https://www.facebook.com/#!/tink.se Linkedin
http://www.linkedin.com/company/2735919?trk=vsrp_companies_res_phototrkInfo=VSRPsearchId%3A1057023381369207406670%2CVSRPtargetId%3A2735919%2CVSRPcmpt%3Aprimary
Twitter https://twitter.com/tink
