data model question : finding out the n most recent changes items

I have an application that need to find out the n most recent modified files for a given user id. I started out few tables but still couldn't get what i want, I hope someone get point to some right direction... See my tables below. #1 won't work, because file_id's timeuuid contains creation time,

Re: Cassandra intermittant with query in 1.2.5...

Ok Robert,   I updated the jira issue you have a link to below. Looks like with Cassandra 1.2.5 you can not use row caching AND column family caching at the same time else queries return with no rows (when there should be) and I suspect inserts fail both with no exceptions thrown.   Regards, -To

Re: General doubts about bootstrap

Thank you very much for you response. Follows my comments about your email. Att. *Rodrigo Felix de Almeida* LSBD - Universidade Federal do Ceará Project Manager MBA, CSM, CSPO, SCJP On Mon, Jul 8, 2013 at 6:05 PM, Robert Coli wrote: > On Sat, Jul 6, 2013 at 1:50 PM, Rodrigo Felix < > rodrigof

Re: alter column family ?

On Tue, Jul 9, 2013 at 11:52 AM, Langston, Jim wrote: > > On the command (4 node cluster): > > nodetool gossipinfo -h localhost |grep SCHEMA |sort | uniq -c | sort -n > 4 SCHEMA:60edeaa8-70a4-3825-90a5-d7746ffa8e4d If your schemas actually agree (and given that you're in 1.1.2) you probab

Re: Leveled Compaction, number of SStables growing.

Since you moved from size tiered compaction. All your sstables are in L0. You might be hitting this. Copied from code. // LevelDB gives each level a score of how much data it contains vs its ideal amount, and // compacts the level with the highest score. But this falls apart spectacularly o

RE: Leveled Compaction, number of SStables growing.

Thanks Sankalp...I will look at these. From: sankalp kohli [mailto:kohlisank...@gmail.com] Sent: Tuesday, July 09, 2013 3:22 PM To: user@cassandra.apache.org Subject: Re: Leveled Compaction, number of SStables growing. Do you have lot of sstables in L0? Since you moved from size tiered compaction

Re: High performance hardware with lot of data per node - Global learning about configuration

I'm curious because we are experimenting with a very similar configuration, what basis did you use for expanding the index_interval to that value? Do you have before and after numbers or was it simply reduction of the heap pressure warnings that you looked for? thanks, Mike On Tue, Jul 9, 2013

Re: Logging Cassandra Reads/Writes

There is a new tracing feature in Cassandra 1.2 that might help you with this. On Tue, Jul 9, 2013 at 1:31 PM, Blair Zajac wrote: > No idea on the logging, I'm pretty new to Cassandra. > > Regards, > Blair > > On Jul 9, 2013, at 12:50 PM, hajjat wrote: > > > Blair, thanks for the clarification!

Re: Logging Cassandra Reads/Writes

No idea on the logging, I'm pretty new to Cassandra. Regards, Blair On Jul 9, 2013, at 12:50 PM, hajjat wrote: > Blair, thanks for the clarification! My friend actually just told me the > same.. > > Any idea on how to do logging?? > > Thanks! > > > > -- > View this message in context: > h

Re: Leveled Compaction, number of SStables growing.

Do you have lot of sstables in L0? Since you moved from size tiered compaction with lot of data, it will take time for it to compact. You might want to increase the compaction settings to speed it up. On Tue, Jul 9, 2013 at 12:33 PM, PARASHAR, BHASKARJYA JAY wrote: > Thanks Jake. Guess we will

Re: Logging Cassandra Reads/Writes

Blair, thanks for the clarification! My friend actually just told me the same.. Any idea on how to do logging?? Thanks! -- View this message in context: http://cassandra-user-incubator-apache-org.3065146.n2.nabble.com/Logging-Cassandra-Reads-Writes-tp7588893p7588896.html Sent from the cassand

RE: Leveled Compaction, number of SStables growing.

Thanks Jake. Guess we will have to increase the size. From: Jake Luciani [mailto:jak...@gmail.com] Sent: Tuesday, July 09, 2013 2:05 PM To: user Subject: Re: Leveled Compaction, number of SStables growing. We run with 128mb some run with 256mb. Leveled compaction creates fixed sized sstables by

Re: Logging Cassandra Reads/Writes

On 07/09/2013 12:25 PM, hajjat wrote: Hi, In a quorum read, my understanding is that Cassandra gets a digest of the object to be read from all nodes, and then chooses the fastest node for retrieving the data (if the quorum is met). According to this talk at Cassandra summit, that's incorrect.

Logging Cassandra Reads/Writes

Hi, In a quorum read, my understanding is that Cassandra gets a digest of the object to be read from all nodes, and then chooses the fastest node for retrieving the data (if the quorum is met). 1) Is it possible to log which node provides the real data in a read operation? 2) Also, is it possi

Re: Leveled Compaction, number of SStables growing.

We run with 128mb some run with 256mb. Leveled compaction creates fixed sized sstables by design so this is the only way to lower the file count. On Tue, Jul 9, 2013 at 2:56 PM, PARASHAR, BHASKARJYA JAY wrote: > Hi, > > ** ** > > We recently switched from size tired compaction to Leveled c

Leveled Compaction, number of SStables growing.

Hi, We recently switched from size tired compaction to Leveled compaction. We made this change because our rows are frequently updated. We also have a lot of data. With size-tiered compaction, we have about 5-10 sstables per CF. So with about 15 CF's we had about 100 sstables. With a sstable def

Re: alter column family ?

On the command (4 node cluster): nodetool gossipinfo -h localhost |grep SCHEMA |sort | uniq -c | sort -n 4 SCHEMA:60edeaa8-70a4-3825-90a5-d7746ffa8e4d On the second part, I have the same Cassandra version in staging and production, with staging being a smaller cluster. Not sure what you m

Re: alter column family ?

On Tue, Jul 9, 2013 at 10:26 AM, Robert Coli wrote: > nodetool -h localhost netstats |grep SCHEMA |sort | uniq -c | sort -n > Sorry, I meant "gossipinfo" and not "netstats". With the right command, do you see that all nodes in the cluster have the same schema version? > I'm on version 1.1.2 >

Re: Trying to write when at cassandra capacity

On Mon, Jul 8, 2013 at 5:58 PM, Faraaz Sareshwala wrote: > What does cassandra do when it is at its data capacity (disk drives and > memtable > is full) and writes continue to pour in? My intuition says that cassandra > won't > be able to handle the new writes (they will either get silently dropp

Re: Node tokens / data move

Hi Aaron, Can he not specify all 256 tokens in the YAML of the new cluster and then copy sstables? I know it is a bit ugly but should work. Sankalp On Tue, Jul 9, 2013 at 3:19 AM, Baskar Duraikannu < baskar.duraikannu...@gmail.com> wrote: > Thanks Aaron > > On 7/9/13, aaron morton

Re: alter column family ?

I'm on version 1.1.2 The nodetool command by itself # nodetool netstats -h localhost Mode: NORMAL Not sending any streams. Not receiving any streams. Pool NameActive Pending Completed Commandsn/a 0 5909 Responses

Re: Migrating data from 2 node cluster to a 3 node cluster

On Tue, Jul 9, 2013 at 12:36 AM, Ananth Gundabattula < agundabatt...@threatmetrix.com> wrote: > > The thread below makes me wonder "Does RF matter when using sstable loader.?" My assumption was that stable loader will take care of RF when the streaming is done but just wanted to cross check. We ar

Re: does anyone store large values in cassandra e.g. 100kb?

yes, by splitting the rows into 36 parts it's very rare that any part gets big enough to impact the clusters performance. there are still rows that are bigger than the in memory compaction limit, but when it's only some it doesn't matter as much. T# On Tue, Jul 9, 2013 at 5:43 PM, S Ahmed wrote

Re: alter column family ?

On Tue, Jul 9, 2013 at 10:08 AM, Langston, Jim wrote: > I am trying to alter a column family to change gc_grace_seconds, and > now, > any of the properties > > The sequence: > > use ks ; > alter table CF with gc_grace_seconds=864000 ; > > When listing the CF, gc_grace_seconds is set to 0, afte

alter column family ?

Hi all, I am trying to alter a column family to change gc_grace_seconds, and now, any of the properties The sequence: use ks ; alter table CF with gc_grace_seconds=864000 ; When listing the CF, gc_grace_seconds is set to 0, after running the CLI, gc_grace_seconds is still set to 0. I tried cha

Re: does anyone store large values in cassandra e.g. 100kb?

So was the point of breaking into 36 parts to bring each row to the 64 or 128mb threshold? On Tue, Jul 9, 2013 at 3:18 AM, Theo Hultberg wrote: > We store objects that are a couple of tens of K, sometimes 100K, and we > store quite a few of these per row, sometimes hundreds of thousands. > > On

Re: bind prepared statement for "IN" select statements

What you are trying to do is not currently supported: https://issues.apache.org/jira/browse/CASSANDRA-4210. That being said, you get that exact error because what you pass to bind() is an array, but bind() is a variadic method, so this is equivalent to writing: ResultSet results = execute(getUse

Re: Purpose of BLOB datatype

> Do you know any direct ways in CQL to handle BLOB, just like DataStax Java driver? Well, CQL3 specification explicitly says that there is no way to encode blob into CQL request other than HEX string: http://cassandra.apache.org/doc/cql3/CQL.html#constants On Tue, Jul 9, 2013 at 6:40 PM, Ollif

bind prepared statement for "IN" select statements

Has anyone tried binding a prepared statement for an "IN" query? For example, protected PreparedStatement getUserInList = prepare(QueryBuilder.select(ADDRESS, USER).from(USER_BY_ADDRESS_COLUMN_FAMILY) .where(QueryBuilder.in(ADDRESS, QueryBuilder.bindMarker(; Object[] addressList

Re: Purpose of BLOB datatype

Thank you for your patience. That is what I have expected. PS. Do you know any direct ways in CQL to handle BLOB, just like DataStax Java driver? On Tue, Jul 9, 2013 at 4:53 PM, Sylvain Lebresne wrote: > > Pls explain why and how. > > Why and how what? > > Not encoding blobs into strings is the

High performance hardware with lot of data per node - Global learning about configuration

Hi, Using C*1.2.2. We recently dropped our 18 m1.xLarge (4CPU, 15GB RAM, 4 Raid-0 Disks) servers to get 3 hi1.4xLarge (16CPU, 60GB RAM, 2 Raid-0 SSD) servers instead, for about the same price. We tried it after reading some benchmark published by Netflix. It is awesome and I recommend it to any

Decommissioned nodes not leaving and Hinted Handoff flood

Hi, C*1.2.2. I have removed 4 nodes with "nodetool decommission". 2 of them have left with no issue, while the 2 others nodes remained "leaving" even after streaming their data. The only specific thing of these 2 nodes is that they had a lot of hints pending. Hints from a node that couldn't come

Re: Node tokens / data move

Thanks Aaron On 7/9/13, aaron morton wrote: >> Can I just copy data files for the required keyspaces, create schema >> manually and run repair? > If you have something like RF 3 and 3 nodes then yes, you can copy the data > from one node in the source cluster to all nodes in the dest cluster and

Re: Working with libcql

yeah I tried that and below is the output I get LOG: resolving remote host localhost:9160 LOG: resolved remote host, attempting to connect LOG: connection successful to remote host LOG: sending message: 0x0105 {version: 0x01, flags: 0x00, stream: 0x00, opcode: 0x05, length: 0} OPTIONS

Re: Purpose of BLOB datatype

> Pls explain why and how. Why and how what? Not encoding blobs into strings is the "preferred way" because that's obviously more efficient (in speed and space), since you don't do any encoding pass. As for how, "use prepared statement" was the "how". What are the exact lines of code to use to d

Re: Migrating data from 2 node cluster to a 3 node cluster

Hello everybody, The thread below makes me wonder "Does RF matter when using sstable loader.?" My assumption was that stable loader will take care of RF when the streaming is done but just wanted to cross check. We are currently moving data from a RF=1 to RF=3 cluster by using sstable loader t

Re: CassandraDaemon - recent unsafe memory access operation in compiled Java code

Hi, Raised here: https://issues.apache.org/jira/browse/CASSANDRA-5737 Am thinking this might be either a kernel bug, or some strange triggering combo on the mmap usage Thanks, Glyn From: aaron morton mailto:aa...@thelastpickle.com>> Reply-To: "user@cassandra.apache.org

Re: does anyone store large values in cassandra e.g. 100kb?

We store objects that are a couple of tens of K, sometimes 100K, and we store quite a few of these per row, sometimes hundreds of thousands. One problem we encountered early was that these rows would become so big that C* couldn't compact the rows in-memory and had to revert to slow two-pass compa