Re: RE: Hector samples -- where?

it's here http://github.com/rantav/hector/blob/master/src/test/java/me/prettyprint/cassandra/service/KeyspaceTest.java On Wed, May 26, 2010 at 8:18 AM, Nicholas Sun wrote: > Could you please provide some indication as to their location? Thanks. > > > > Nick > > > > *From:* Ran Tavory [mailto:r

RE: RE: Hector samples -- where?

Thanks All, I found it here: http://code.google.com/p/cassandra-java-client/source/browse/trunk/src/test/java/org/yosemite/jcsadra/impl/KeySpaceTest.java?r=50 I’m actually fairly new to OSS, but I wanted to really dig into the software here. So far, so good. Nick Fro

RE: RE: Hector samples -- where?

Could you please provide some indication as to their location? Thanks. Nick From: Ran Tavory [mailto:ran...@gmail.com] Sent: Tuesday, May 25, 2010 9:15 PM To: user@cassandra.apache.org Subject: Re: RE: Hector samples -- where? The best examples are in KeyspaceTest but don't include al

Re: RE: Hector samples -- where?

The best examples are in KeyspaceTest but don't include all scenarios On May 26, 2010 2:27 AM, "Nicholas Sun" wrote: I am also interested in this. It seems like adding multiple Cols into a CF or SuperCols would be very useful. Like a dataload type capability? Nick -Original Message-

Cassandra-0.6.1 Crash Error: out of memory

Hi There are 3 Cassandra servcer runing, and 18 process insert lots of data into the Cassandra servcer. After runing for an hour the Cassandra servcer crashed. The error msg is below: INFO [GC inspection] 2010-05-26 00:56:50,153 GCInspector.java (line 110) GC for ConcurrentMarkSweep: 7764 ms

Re: Problem accessing Cassandra wiki top page with browser locale other than english

Jonathan, Thanks for reporting an issue. I will wait and see. 2010年5月25日23:29 Jonathan Ellis : > Turns out this is a bug in the version of MoinMoin the ASF has > installed.  There's nothing we can do until the infrastructure team > upgrades: https://issues.apache.org/jira/browse/INFRA-2741 > > On

Order Preserving Partitioner

I have a question on using Order Preserving Partitioner. Many rowKeys in my system will be related to dates, so it seems natural to use Order Preserving Partitioner instead of the default Random Partitioner. However, I have been warned that special attention has to be applied for Order Preserving

GMFD messages

Hi, I just noticed I have lots of these messages INFO [GMFD:1] 2010-05-25 23:21:04,070 GossipDigestSynMessage.java (line 152) Remaining bytes zero. Stopping deserialization in EndPointState. INFO [GMFD:1] 2010-05-25 23:21:05,224 GossipDigestSynMessage.java (line 129) Breaking out to re

RE: Hector samples -- where?

I am also interested in this. It seems like adding multiple Cols into a CF or SuperCols would be very useful. Like a dataload type capability? Nick -Original Message- From: Bill de hOra [mailto:b...@dehora.net] Sent: Tuesday, May 25, 2010 3:18 PM To: user@cassandra.apache.org Subject:

Re: Why are writes faster than reads?

On 25 May 2010 09:04, David Boxenhorn wrote: > I have seen several off-hand mentions that writes are inherently faster > than reads. Why is this so? > In addition to the points that other posters made, writes only need to go as far as your battery-backed raid controller, whereas reads go all the

Re: Why are writes faster than reads?

Writes only have to write to the journal before returning. Reads have to read potentially from several sources, including binary searches of things that may or may not be cached anywhere. The journal writes do not involve much random disk IO, while the read activity does. On Tue, May 25, 2010 at

Re: Hector samples -- where?

Are there examples of inserting multiple cols into a CF anywhere? Bill Ran Tavory wrote: http://wiki.github.com/rantav/hector/examples On May 25, 2010 10:43 PM, "Asaf Lahav" > wrote: Hi, Where can I find Hector code samples?

Re: Hector samples -- where?

10x On Tue, May 25, 2010 at 10:45 PM, Ran Tavory wrote: > http://wiki.github.com/rantav/hector/examples > > On May 25, 2010 10:43 PM, "Asaf Lahav" wrote: > > Hi, Where can I find Hector code samples? > > >

Re: Hector vs cassandra-java-client

Hello I've used jassandra, works fine and easy for use. On 25.05.2010 06:21, Peter Hsu wrote: Hi All, This may have been answered already, but I did a [quick] Google search and didn't find much. Which is the better Java client to use? Hector or cassandra-java-client or neither? it seems H

Re: Hector samples -- where?

http://wiki.github.com/rantav/hector/examples On May 25, 2010 10:43 PM, "Asaf Lahav" wrote: Hi, Where can I find Hector code samples?

Hector samples -- where?

Hi, Where can I find Hector code samples?

Re: Why Cassandra is "space inefficient" compared to MySQL?

Yes. But I haven't yet seen a workload with enough data that that would matter, that wasn't more cpu bound than disk space bound, so that would usually be premature optimization. On Tue, May 25, 2010 at 2:23 PM, Robert Edmonds wrote: > On 2010-05-25, Jonathan Ellis wrote: >> That's true.  But f

Re: Why Cassandra is "space inefficient" compared to MySQL?

On 2010-05-25, Jonathan Ellis wrote: > That's true. But fundamentally Cassandra is expected to use more > space than mysql for a few reasons; usually the biggest factor is that > Cassandra has to write out each column name in each row, since column > names are dynamic unlike in mysql where you de

Re: Panasas and Cassandra

Two reasons: Do a single node test of large file read/write without having to purchase additional hard rives at the moment. Benefit from I/O Panasas delivers that I can't get from local drives... Keeping the data local, for easier loading. On 5/25/10 11:58 AM, "Ryan King" wrote: > On Tue, M

Re: Why Cassandra is "space inefficient" compared to MySQL?

the only place we use a java serializer is for the BitSet in bloom filters. On Tue, May 25, 2010 at 12:37 PM, Chris Goffinet wrote: > My money is on the fact that the serializer is just horribly verbose. It's > using a basic set of the java serializer. > -Chris > > > On Tue, May 25, 2010 at 10:02

Re: Anyone using hadoop/MapReduce integration currently?

Hi Jeremy, > Why are you using Cassandra versus using data stored in HDFS or HBase? - I'm thinking of using it for realtime streaming of user data. While streaming the requests, I'm also using Lucandra for indexing the data in realtime. It's a better option when you compare it with HBase or the na

Re: Why Cassandra is "space inefficient" compared to MySQL?

My money is on the fact that the serializer is just horribly verbose. It's using a basic set of the java serializer. -Chris On Tue, May 25, 2010 at 10:02 AM, Ryan King wrote: > Also, timestamps for each column. > > -ryan > > On Tue, May 25, 2010 at 5:41 AM, Jonathan Ellis wrote: > > That's tr

Re: Key cache capacity: 1 when using KeysCached="50%"

https://issues.apache.org/jira/browse/CASSANDRA-1129 On Tue, May 25, 2010 at 3:42 PM, Jonathan Ellis wrote: > That does look like a bug. Can you create a ticket and upload a > (preferably small-ish) sstable that illustrates the problem? > > On Mon, May 24, 2010 at 12:07 PM, Ran Tavory wrote:

Re: Why Cassandra is "space inefficient" compared to MySQL?

Also, timestamps for each column. -ryan On Tue, May 25, 2010 at 5:41 AM, Jonathan Ellis wrote: > That's true.  But fundamentally Cassandra is expected to use more > space than mysql for a few reasons; usually the biggest factor is that > Cassandra has to write out each column name in each row, s

Re: Panasas and Cassandra

On Tue, May 25, 2010 at 9:06 AM, Fernanda Foertter wrote: > Hi everyone, > > So we have Panasas (http://www.panasas.com), and want to avoid local drives. >  Because panasas has its own redundancy and cache, Can I set RF=1?  If so, > can you think of any reason why we shouldn’t use panasas? I don'

Re: Why are writes faster than reads?

On Tue, May 25, 2010 at 4:04 AM, Mark Greene wrote: > I'm fairly certain the write path hits the commit log first, then the > memtable. True, but that does not make them any less sequential -- journal logs are strictly sequential fast writes. Actual ordering occurs in memory, and results are even

Anyone using hadoop/MapReduce integration currently?

I'll be doing a presentation on Cassandra's (0.6+) hadoop integration next week. Is anyone currently using MapReduce or the initial Pig integration? (If you're unaware of such integration, see http://wiki.apache.org/cassandra/HadoopSupport) If so, could you post to this thread on how you're usi

RE: high-scale-lib & clhm-production jars

Thanks a lot From: Tobias Jungen [mailto:tobias.jun...@gmail.com] Sent: Tuesday, May 25, 2010 10:56 AM To: user@cassandra.apache.org Subject: Re: high-scale-lib & clhm-production jars High-scale-lib: http://sourceforge.net/projects/high-scale-lib/ CLHM: http://code.google.com/p/concurrentlinkedha

Panasas and Cassandra

Hi everyone, So we have Panasas (http://www.panasas.com), and want to avoid local drives. Because panasas has its own redundancy and cache, Can I set RF=1? If so, can you think of any reason why we shouldn¹t use panasas? Thanks in advance ŒFernie¹

Re: high-scale-lib & clhm-production jars

High-scale-lib: http://sourceforge.net/projects/high-scale-lib/ CLHM: http://code.google.com/p/concurrentlinkedhashmap/ On Tue, May 25, 2010 at 10:17 AM, Carlos Sanchez < carlos.sanc...@riskmetrics.com> wrote: > Do anyone know if there are repositories for high-scale-lib & > clhm-production jars?

RE: Nunit Testing & Cassandra

A great suggestion. I tried what you have mentioned. They are not equal. I get the same error. Thanks for your help. I appreciate it. From: Miguel Verde [mailto:miguelitov...@gmail.com] Sent: Tuesday, May 25, 2010 11:07 AM To: user@cassandra.apache.org Cc: user@cassandra.apache.org Subject: Re

high-scale-lib & clhm-production jars

Do anyone know if there are repositories for high-scale-lib & clhm-production jars? Is the source available somewhere? Thanks Carlos This email message and any attachments are for the sole use of the intended recipients and may contain proprietary and/or confidential information which may be

Re: Nunit Testing & Cassandra

My guess is that it is using object equality to compare. One thing to test would be to create two KeySlices whose contents had the same values, add them to separate lists, and then compare the lists. I think you'll find that they are not 'equivalent'. On May 25, 2010, at 10:00 AM, Sandeep

RE: Nunit Testing & Cassandra

SDSWebService.Service1Test.GetListOfRowKeysFromCF: Expected: equivalent to < , , , > But was: < , , , > Is.EquivalentTo( ICollection ) - tests that two collections are equivalent. Two collections are equivalent if they contain the same items, in any order. Assert.That(listOfKey

Re: get() with TTL update?

On Mon, May 24, 2010 at 4:53 PM, Jonathan Ellis wrote: > (a) cassandra does not use update-in-place storage so doing the update > as part of the get call isn't much of an efficiency gain If you could issue an "update" type of command, any other data needed for the new copy of the object could be

Re: Problem accessing Cassandra wiki top page with browser locale other than english

Turns out this is a bug in the version of MoinMoin the ASF has installed. There's nothing we can do until the infrastructure team upgrades: https://issues.apache.org/jira/browse/INFRA-2741 On Sun, May 23, 2010 at 10:09 PM, Yuki Morishita wrote: > Hi all, > > I'm currently working on translating

RE: Hector vs cassandra-java-client

Updated. Cheers~ Dop -Original Message- From: Jonathan Ellis [mailto:jbel...@gmail.com] Sent: Tuesday, May 25, 2010 8:39 PM To: user@cassandra.apache.org Subject: Re: Hector vs cassandra-java-client You should link it on http://wiki.apache.org/cassandra/ClientOptions (click Login to edi

Re: Nunit Testing & Cassandra

It would be helpful to know in what way the test fails, or more information about listOfKeys or the return value of GetListOfRowKeysFromCF at assert time, or for that matter what GetListOfRowKeysFromCF is, or the insertion code. Also, does Is.EquivalentTo compare object equality on the items insid

Nunit Testing & Cassandra

Hi all, I am recent grad and working on Cassandra and Nunit testing. I wrote a unit test in C# which goes like this List listOfKeys = new List(); KeySlice item1 = new KeySlice(); KeySlice item2 = new KeySlice(); KeySlice item3 = new KeySlice();

Re: Cassandra configuration settings

If you don't know what your workload bottlenecks are, the defaults are fine. On Tue, May 25, 2010 at 5:05 AM, sharanabasava raddi wrote: > Hi All, > Could u please give configuration settings for "single node"(Windows > machine), so that it must be "time and space efficient". > > > > > > Thanks,

Re: Error reporting Key cache hit rate with cfstats or with JMX

What happens if you disable row cache? On Tue, May 25, 2010 at 4:53 AM, Ran Tavory wrote: > It seems there's an error reporting the Key cache hit rate. The value is > always 0.0 and I have a feeling it's incorrect. This is seen both by using > notetool cfstats as well as accessing JMX directly >

Re: Key cache capacity: 1 when using KeysCached="50%"

That does look like a bug. Can you create a ticket and upload a (preferably small-ish) sstable that illustrates the problem? On Mon, May 24, 2010 at 12:07 PM, Ran Tavory wrote: > I'd like to have 100% keys cached. Sorry if my example of Super2 wasn't > correct, but I do think there's a problem.

Re: Why Cassandra is "space inefficient" compared to MySQL?

That's true. But fundamentally Cassandra is expected to use more space than mysql for a few reasons; usually the biggest factor is that Cassandra has to write out each column name in each row, since column names are dynamic unlike in mysql where you declare the columns once for the whole table. 2

Re: Hector vs cassandra-java-client

You should link it on http://wiki.apache.org/cassandra/ClientOptions (click Login to edit) On Tue, May 25, 2010 at 2:12 AM, Dop Sun wrote: > A good chance to introduce my http://code.google.com/p/jassandra/ > > > > J > > > > Another Java client, and well, it cannot be found with Cassandra java cl

Re: Why are writes faster than reads?

> I'm fairly certain the write path hits the commit log first, then the > memtable. I didn't mean to imply an ordering between the two (I probably should not have said "memtable plus commit log"...), and yes I believe so. -- / Peter Schuller aka scode

Re: Why are writes faster than reads?

I'm fairly certain the write path hits the commit log first, then the memtable. 2010/5/25 Peter Schüller > > I have seen several off-hand mentions that writes are inherently faster > than > > reads. Why is this so? > > I believe the primary factor people are referring to is that writes > are fas

Cassandra configuration settings

Hi All, Could u please give configuration settings for "single node"(Windows machine), so that it must be "time and space efficient". Thanks, Sharan

Error reporting Key cache hit rate with cfstats or with JMX

It seems there's an error reporting the Key cache hit rate. The value is always 0.0 and I have a feeling it's incorrect. This is seen both by using notetool cfstats as well as accessing JMX directly (org.apache.cassandra.db:type=Caches,keyspace=outbrain_kvdb,cache=KvAdsKeyCache RecentHitRate)

Re: Why Cassandra is "space inefficient" compared to MySQL?

Hi Peter, Thanks a lot. Regards, Sharan 2010/5/25 Peter Schüller > > Could you please tell me why? > > There might be pending sstable removals on disk, which won't happen > until GC or restart. If you just did a bulk insert and checked > diskspace immediately afterwards, I think this is a pos

Re: Why are writes faster than reads?

> I have seen several off-hand mentions that writes are inherently faster than > reads. Why is this so? I believe the primary factor people are referring to is that writes are faster than reads in terms of disk I/O because writes are inherently sequential. Writes initially only happen in-memory pl

Why are writes faster than reads?

I have seen several off-hand mentions that writes are inherently faster than reads. Why is this so?

Re: Why Cassandra is "space inefficient" compared to MySQL?

> Could you please tell me why? There might be pending sstable removals on disk, which won't happen until GC or restart. If you just did a bulk insert and checked diskspace immediately afterwards, I think this is a possible explanation. (See "Write path" on http://wiki.apache.org/cassandra/Archit

Re: Why Cassandra is "space inefficient" compared to MySQL?

Hi Cao, Thanks for your response. actually am using ReplicationFactor = 1. Thanks, Sharan 2010/5/25 casablinca126.com > hi Sharan, > what's the replication factor are you using ? > > regards, > Cao Jiguang > > > 2010-05-25 > -- > casablinca126.com > ---

RE: Hector vs cassandra-java-client

A good chance to introduce my http://code.google.com/p/jassandra/ J Another Java client, and well, it cannot be found with Cassandra java client keywords. K From: Ran Tavory [mailto:ran...@gmail.com] Sent: Tuesday, May 25, 2010 2:52 PM To: user@cassandra.apache.org Subject: Re: Hector