get_slice wont let me page backwards.

Hi, I've been trying to write a wrapper around get_slice that supports paging semantics. I can get it to page forwards - starting with Start="" and then successively passing in a new Start / Count. But when i try going backwards from the end, passing Start = "" and Finish = "X", it doesn't give

Re: client connecting to 0.7

I agree and we will move to hector at some point, but we have some legacy code we need to convert to the new api. What am I doing wrong in the code I posted? On Fri, Nov 5, 2010 at 5:45 PM, Jonathan Ellis wrote: > From Java you should be using Hector instead of messing around with > raw Thrif

node won't leave

In the below "nodetool ring" output, machine 18 was told to loadbalance over an hour ago. It won't actually leave the ring. When I first told it to loadbalance, the cluster was under heavy write load; I've turned off the write load, but the node won't actually leave, still. Help? (It also colle

Re: client connecting to 0.7

>From Java you should be using Hector instead of messing around with raw Thrift. There is a version for beta2 at https://github.com/rantav/hector/downloads docs are at http://www.riptano.com/sites/default/files/hector-v2-client-doc.pdf On Fri, Nov 5, 2010 at 6:28 PM, CassUser CassUser wrote: >

Re: Long connections to cassandra

No. You should be looking for errors in the server logs or hs_err_pid log files (which would indicate a JVM crash). On Fri, Nov 5, 2010 at 6:49 PM, Paula Lago wrote: > Hi, > I have a program that recolects a lot of information and is kept running > over long time periods (various days) so the co

Long connections to cassandra

Hi, I have a program that recolects a lot of information and is kept running over long time periods (various days) so the connection to the database are kept open for this long. I'm experiencing falls in cassandra (the server stops) and I wanted to know if it could be due to this long connections.

client connecting to 0.7

Hey I'm testing a client on beta2 cassandra version 0.7. TFramedTransport transport = new TFramedTransport(new TSocket("my.ip", 9160)); Cassandra.Client client = new Cassandra.Client(new TBinaryProtocol(transport)); transport.open(); System.out.println(client.descri

Key to Token clarification

Hi all, I'm trying to figure out some minor understanding problems. As I see it for each Keyspace each node takes care about a certain tokenRange (describe_ring gives me the assignment), these TokenRanges have a list of nodes that hold replicas, a start token and an end token. The tokens are of ty

Re: row cache vs frequent row updates vs write through row cache

On Fri, Nov 5, 2010 at 2:41 PM, Jeremy Davis wrote: > What do you mean by "Turning Over quickly"? What is Turning over? If it > needs to create an entirely new row, then that would create GC pressure for > sure... But if you are just updating a column in a row that is already in > the cache, then

Re: row cache vs frequent row updates vs write through row cache

> In short, it seems like the general advice is unless you have a set of nearly > static rows, AND they all fit in the cache, then rowcache is not recommended. That's been our experience. Leave the memory for the OS cache instead. Dave On Friday, November 5, 2010, Jeremy Davis wrote: > What do

Re: row cache vs frequent row updates vs write through row cache

What do you mean by "Turning Over quickly"? What is Turning over? If it needs to create an entirely new row, then that would create GC pressure for sure... But if you are just updating a column in a row that is already in the cache, then I would think that would be the optimal situation. OTOH, you

Re: Cassandra Hadoop Integration not compatible with Hadoop 0.21.0

I'm not sure of the specific error but you may not want to be using 0.21. "23 August, 2010: release 0.21.0 available This release contains many improvements, new features, bug fixes and optimizations. It has not undergone testing at scale and should not be considered stable or suitable for produ

Re: row cache vs frequent row updates vs write through row cache

On Fri, Nov 5, 2010 at 1:41 PM, Jeremy Davis wrote: > I saw in the Riptano "Tuning Cassandra" slide deck that the row cache can > be detrimental if there are a lot of updates to the cached row. Is this > because the cache is not write through, and every update necessitates > creation of a new row?

row cache vs frequent row updates vs write through row cache

I saw in the Riptano "Tuning Cassandra" slide deck that the row cache can be detrimental if there are a lot of updates to the cached row. Is this because the cache is not write through, and every update necessitates creation of a new row? I see there is an open issue: https://issues.apache.org/jira

Cassandra Hadoop Integration not compatible with Hadoop 0.21.0

When I try to read a CF from Hadoop, just after issuing the run I get this error: Exception in thread "main" java.lang.IncompatibleClassChangeError: Found interface org.apache.hadoop.mapreduce.JobContext, but class was expected at org.apache.cassandra.hadoop.ColumnFamilyInputFormat.getSpli

Re: RE: how does get_range_slices work?

No,It's not the columns, but the rows. These are the keys of the rows. -- zangds 2010-11-05 - 发件人：Stu Hood 发送日期：2010-11-05 17:07:43 收件人：user 抄送： 主题：RE: how does get_range_slices work? What

RE: Merkle trees

The actually MerkleTree itself is at org.apache.cassandra.utils.MerkleTree: it has a reasonable number of tests in the MerkleTreeTest class, and Cassandra uses a tree to store the hashes of a ColumnFamily in o.a.c.d.CompactionManager via a o.a.c.s.AntiEntropyService "Validator". -Original

RE: how does get_range_slices work?

What column comparator/type are you using? Remember that if you are using BytesType/UTF8Type, columns will be sorted lexicographically. -Original Message- From: "zangds" Sent: Friday, November 5, 2010 8:53am To: "user" Subject: how does get_range_slices work? Hi, I have a question ab

Merkle trees

All, Is there a good resource to learn about merkle trees and its implementation in Cassandra? What classes should I be looking at. Thx a lot Carlos This email message and any attachments are for the sole use of the intended recipients and may contain proprietary and/or confidential informatio

Re: SSD vs. HDD

If you're experiencing high I/O load and not getting any Java OutOfMemory (OOM) errors, you should try to keep your heap size as low as possible as this provides the OS filesystem cache with more memory, which will reduce read I/O load significantly. I'm not familiar the performance of Windows file

Fwd: read timeouts in cassandra 0.6.5

Hi, I have a simple keyspace: org.apache.cassandra.locator.RackUnawareStrategy 1 org.apache.cassandra.locator.EndPointSnitch We're using it as a data historian. Many rows of measurments, measurement history is in the columns by milliseconds since UNIX epoch. The single nod

Re: default_validation_class and column_metadata

Yes, but not until beta3. On Fri, Nov 5, 2010 at 8:17 AM, zangds wrote: > Hi, > Is it possible to use default_validation_class and column_metadata in > cassandra-cli? > I'm using 0.7.0-beta2. > Thanks! > > 2010-11-05 > > zangds -- Jonathan Ellis Project Chair,

how does get_range_slices work?

Hi, I have a question about the get_range_slices() function about the key sorting. I inserted some colums with keys of '1', '2' ,'7' and '10'. When I use get_range_slices to get colums betwen '1' and '10' , I got none. But When I get colums betwen '10' and '1', I got '10', '2' and '1'. Can anybody

default_validation_class and column_metadata

Hi, Is it possible to use default_validation_class and column_metadata in cassandra-cli? I'm using 0.7.0-beta2. Thanks! 2010-11-05 zangds

Re: getRange - Cassandra

Hi Nate, ok for write to email groups for hector. I'll tell you this row 'eeg' is not in my results: This is what i see: cassandra> get liquida_en.Tag2CatLoc['eeg'] Returned 0 results. cassandra> get liquida_en.Tag2CatLoc['apple'] => (column=id, value=4744, timestamp=1288875937498611) => (column