I'm wondering if anyone can suggest the best resources for Java based
Cassandra access. I've been able to create a client that can create data
and retrieve a row but I'm struggling to understand how to setup queries
based on criteria (e.g. return all keys that have a the field "color"
equal to "red
I can offer Hector which I've authored and maintain with the help of a few
other folks
http://wiki.github.com/rantav/hector/
http://github.com/rantav/hector
Feel free to post questions to our mailing list
http://groups.google.com/group/hector-users
On Thu, Jun 17, 2010 at 10:04 AM, Anthony Ikeda
On Thu, Jun 17, 2010 at 1:20 AM, Anthony Ikeda
wrote:
> Thanks Gary, I’m looking at that plug-in feature at the moment but there
> seems to be very little documentation on how to use it.
There is no documentation whatsoever. This is just a feature proposition right
now (it's not included in Cassa
If new to cassandra, how it achieves its goals etc., I would recommend going
with the "raw" thrift API to start with, until you get a good understanding of
which API calls there are and how they work. I am sure there are nicer APIs,
but they also somewhat hide some of the complexity, that I thin
Hi Anthony,
As I understand it Cassandra, like most other "no SQL" alternative
data stores does not support arbitrary queries. Translation: you can't
directly query by field (that is to say, column) value. You are left
with doing a "row scan" client side. Hence you need to know what
queri
I'm seing 10s timeouts on reads few times a day. Its hard to reproduce
consistently but seems to happen most often after its been a long time
between reads. After presenting itself for a couple minutes the
problem then goes away.
I've got a three node cluster with replication factor 2, reading at
Cassandra 0.6.2 from the apache debian source.
Ubunutu Jaunty. Sun Java6 jvm.
All nodes in separate racks at 365 main.
On Thu, Jun 17, 2010 at 10:12 AM, AJ Slater wrote:
> I'm seing 10s timeouts on reads few times a day. Its hard to reproduce
> consistently but seems to happen most often after i
Total data size in the entire cluster is about twenty 12k images. With
no other load on the system. I just ask for one column and I get these
timeouts. Performing multiple gets on the columns leads to multiple
timeouts for a period of a few seconds or minutes and then the
situation magically resolv
Hi,
Being fairly new to Cassandra I have a couple of questions:
1) Is there a way to remove multiple keys/rows in one operation (batch) or must
keys be removed one by one?
2) I see API references to version 0.7, but I couldn't find a alpha or beta
anywhere? Does it exist already and if so, wher
On Thu, Jun 17, 2010 at 9:09 PM, F. Hugo Zwaal wrote:
> Hi,
>
> Being fairly new to Cassandra I have a couple of questions:
>
> 1) Is there a way to remove multiple keys/rows in one operation (batch) or
> must keys be removed one by one?
>
yes, batch_mutate
> 2) I see API references to version 0
Columnar data stores like Cassandra require you to construct indices to
answer the queries of interest to you.
http://www.slideshare.net/benjaminblack/cassandra-basics-indexing
On Thu, Jun 17, 2010 at 12:04 AM, Anthony Ikeda <
anthony.ik...@cardlink.com.au> wrote:
> I’m wondering if anyone can s
+ user, - dev (bcc actually)
If you use a random partitioner use the following InitialToken for your
nodes:
$ bc
bc 1.06
Copyright 1991-1994, 1997, 1998, 2000 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'.
(2^127)/3
*5671372782015641
Hello!
I am trying to rework our current lucene-based application to lucandra.
Note the following problem: when I try to use NumericRangeQuery like
this one:
query.add(NumericRangeQuery.newLongRange("deliveryTimestampMinute", 6,
fromDate, toDate, true, true), BooleanClause.Occur.MUST);
I got
jmx does this fun thing where the node you're connecting to, connects
back to jconsole over a random port:
http://blogs.sun.com/jmxetc/entry/connecting_through_firewall_using_jmx
On Wed, Jun 16, 2010 at 7:34 AM, wrote:
> I am trying to set up replication among three cassandra nodes. I believe it
Do you have Row Caching enabled ? You can check in the JMX console to see if
you're hitting the cache.
Try turning on DEBUG level logging and look at the log on a machine you
connect to do the read.
Aaron
On 18 Jun 2010, at 05:31, AJ Slater wrote:
> Total data size in the entire cluster i
That looks pretty normal to me. The JVM doesn't do a full GC until
the old gen crosses a (dynamic, defaults to about 70% of heap)
threshold.
On Thu, Jun 17, 2010 at 1:01 PM, Mike Subelsky wrote:
> I just started munin to monitor the performance of my cluster which is
> working great. I noticed
> drive on an EBS volume). Does that pattern look bad or is it
> relatively normal? If it's not normal, any advice for what I should
> change to get better performance?
Assuming you're running with the default cassandra VM options or
similar (mainly, the CMS GC), the graph looks fairly normal to
The explanation that best fits the symptoms you describe is that you
are swapping.
On Thu, Jun 17, 2010 at 10:12 AM, AJ Slater wrote:
> I'm seing 10s timeouts on reads few times a day. Its hard to reproduce
> consistently but seems to happen most often after its been a long time
> between reads.
On Thu, Jun 17, 2010 at 04:01:41PM -0400, Mike Subelsky wrote:
> I just started munin to monitor the performance of my cluster which is
> working great. I noticed the attached pattern for JVM heap size -
> lots of peaks and valleys, which looks like GC is firing pretty
> frequently. I don't have
T
On Thu, Jun 17, 2010 at 4:53 PM, Peter Schuller
wrote:
>> drive on an EBS volume). Does that pattern look bad or is it
>> relatively normal? If it's not normal, any advice for what I should
>> change to get better performance?
>
> Assuming you're running with the default cassandra VM options o
Are these physical machines or virtuals? Did you post your
cassandra.in.sh and storage-conf.xml someplace?
On Thu, Jun 17, 2010 at 10:31 AM, AJ Slater wrote:
> Total data size in the entire cluster is about twenty 12k images. With
> no other load on the system. I just ask for one column and I ge
The behavior was seen with row caching off.
I now have row caching on.
key cache hit rate is 0.75-0.8
row cache hit rate is 0 (row cache capacity=1, RowsCached="100%")
looks like I should try another format for RowsCached, like "0.8" or
"90%" or something.
On Thu, Jun 17, 2010 at 1:47 PM, aaron
The machines in question have 8GB of RAM each and generally never touch swap.
I shall try to monitor memory/swap overnight and see if something
strange happens.
Would swapping really take 10s?
AJ
On Thu, Jun 17, 2010 at 1:54 PM, Jonathan Ellis wrote:
> The explanation that best fits the symptom
These are physical machines.
storage-conf.xml.fs03 is here:
http://pastebin.com/weL41NB1
Diffs from that for the other two storage-confs are inline here:
a...@worm:../Z3/cassandra/conf/dev$ diff storage-conf.xml.lpc03
storage-conf.xml.fs01
185c185
> 71603818521973537678586548668074777838
229
Any plans for this sort of call?
Instead of:
public Map> multiget_slice(String
keyspace, List keys, ColumnParent column_parent,
SlicePredicate predicate, ConsistencyLevel consistency_level) throws
InvalidRequestException, UnavailableException, TimedOutException,
TException;
---
public
Thanks Sylvia, I would like to actually do that actually. Any idea how I can
get started?
-Original Message-
From: Sylvain Lebresne [mailto:sylv...@yakaz.com]
Sent: Thursday, 17 June 2010 5:46 PM
To: user@cassandra.apache.org
Subject: Re: Some questions about using Cassandra
On Thu, Jun
Okay, so that is where frameworks such as Lucene come into play.
Right now we have set up Cassandra and are trying to come up with the best
schema, per se, that is going to be the most effective and I think I’ll need to
start looking at something like Lucene to ensure the model can be more vi
HI All,
I have a requirement that we have around 100 application server instances and
all needs to write/read data from cassandra's cluster, the write data rate is
around 300k records per instance (approximately 30 millions for 100 instances).
- How does client (application) connect to cassandr
No. At that point you basically have no overhead advantage vs just
doing multiple single-row requests.
On Thu, Jun 17, 2010 at 2:39 PM, Sonny Heer wrote:
> Any plans for this sort of call?
>
>
> Instead of:
>
> public Map> multiget_slice(String
> keyspace, List keys, ColumnParent column_paren
Is there any way at all (In Java) to get all the data from a
ColumnFamily?
I've inserted data into Cassandra and I don't seem to have a way to
browse what's in there.
Anthony Ikeda
Java Analyst/Programmer
Cardlink Services Limited
Level 4, 3 Rider Boulevard
Rhodes NSW 2138
Web: www.
probably Cassandra isn't configured to use thrift framed mode, which
Chiton requires.
On Wed, Jun 16, 2010 at 3:29 PM, John Schneider wrote:
> Hi,
> I've got Chiton comming up on a mac, however when I connect to my Cassandra
> instance, it never comes back from "Fetching keyspaces..."
>
> Log fro
you either need to use OPP and issue a get_range() request with empty
strings for start and end keys (and you'll generally want to paginate using
a count option and saving the last entry in a given page), or you need to
index your rows. same as with any other sort of query you might want to
perfor
look at get_range_slices in http://wiki.apache.org/cassandra/API
On Thu, Jun 17, 2010 at 6:36 PM, Anthony Ikeda <
anthony.ik...@cardlink.com.au> wrote:
> Is there any way at all (In Java) to get all the data from a
> ColumnFamily?
>
>
>
> I’ve inserted data into Cassandra and I don’t seem to hav
Lucandra is not a framework, it is Lucene on top of Cassandra. You
seem to be falling into the most common trap for relational folks
coming to column stores: trying to model your _data_ instead of trying
to model your _queries_. You _must_ use the tools as intended to
achieve good results.
b
O
You download the patch and apply it.
On Thu, Jun 17, 2010 at 4:10 PM, Anthony Ikeda
wrote:
> Thanks Sylvia, I would like to actually do that actually. Any idea how I can
> get started?
>
> -Original Message-
> From: Sylvain Lebresne [mailto:sylv...@yakaz.com]
> Sent: Thursday, 17 June 20
I'm certain I didn't mention Lucandra, but yes I get the idea about the
concepts:
* Use indexing tool to reference with queries that returns keys
* Store and retrieve data from Cassandra by the keys
Anthony
-Original Message-
From: Benjamin Black [mailto:b...@b3k.us]
Sent: Friday, 18 Ju
Great thanks! I'm slowly getting the hang of all this now.
From: Benjamin Black [mailto:b...@b3k.us]
Sent: Friday, 18 June 2010 1:07 PM
To: user@cassandra.apache.org
Subject: Re: Get all rows back from a ColumnFamily
you either need to use OPP and issue a get_range() request with empty
On Thu, Jun 17, 2010 at 9:00 PM, Anthony Ikeda
wrote:
> I'm certain I didn't mention Lucandra, but yes I get the idea about the
> concepts:
Lucandra is Lucene on Cassandra. Unclear to me how else Lucene is
relevant, but, ok!
> * Use indexing tool to reference with queries that returns keys
> *
Jonathan - correct.
Brandon clued me in that framed mode was required and it woke right up
when I booted in framed mode.
Tnx,
jos
On Thu, Jun 17, 2010 at 7:47 PM, Jonathan Ellis wrote:
> probably Cassandra isn't configured to use thrift framed mode, which
> Chiton requires.
>
> On Wed, Jun 16,
Hi
Is the client API for cassandra available in AVRO. If so, any links to
examples or some documentation ?
and If so, any comparison between Thrift and Avro API's to determine the
better of them ?
Thanks
Atul
40 matches
Mail list logo
