Re: how to implement a client with off-heap memory

The thrift client is just auto generated code, if you really wanted to you may be able to change / override it to modify the SerDe when it pulls things off the wire. Not sure if this does what you are looking for https://issues.apache.org/jira/browse/CASSANDRA-2478 Cheers - A

Re: High bandwidth usage between datacenters for cluster

Outbound messages for other DC's are grouped and a single instance is sent to a single node in the remote DC. The remote node then forwards the message on to the other recipients in it's DC. All remote DC nodes will however reply directly to the coordinator. > Normally this isn’t an issue for u

Re: Roadmap/Changelog?

For committed changes https://github.com/apache/cassandra/blob/trunk/CHANGES.txt For interesting changer per release https://github.com/apache/cassandra/blob/trunk/NEWS.txt For the road map https://issues.apache.org/jira/browse/CASSANDRA#selectedTab=com.atlassian.jira.plugin.system.project%3Aro

Re: compression

Hi! Thanks Aaron! Today I restarted Cassandra on that node and ran scrub again, now it is fine. I am worried though that if I decide to change another CF to use compression I will have that issue again. Any clue how to avoid it? Thanks. *Tamar Fraenkel * Senior Software Engineer, TOK Media [ima

Re: Hinted Handoff storage inflation

> With both data centers functional, the test takes just a few minutes to run, > with one data center down, 15x the amount of time. Could you provide the numbers, it's easier to get a feel for how the throughput is dropping. Does latency reported by nodetool cf stats change ? I'm also interested

Re: compression

name => date#event, data => counter (date format 20121029). 2 - Is it a good Idea to compress this kind of data ? I am looking for using composites columns. 3 - What are the benefits of using a column name like "CompositeType(UTF8Type, UTF8Type)" and a simple UTF8 column with

CQL3: Unknown property 'comparator'?

Does CQL3 not allow dynamic columns (column names) any more?

Re: CQL3: Unknown property 'comparator'?

CQL3 does absolutely allow dynamic column families, but does it differently from CQL2. See http://www.datastax.com/dev/blog/cql3-for-cassandra-experts. -- Sylvain On Mon, Oct 29, 2012 at 12:34 PM, Timmy Turner wrote: > Does CQL3 not allow dynamic columns (column names) any more?

Re: CQL3: Unknown property 'comparator'?

Thank you! That article helps clear up a lot of my confusion about the changes between CQL 2 and 3, since I was wondering how to access/manipulate CompositeType/DynamicCompositeType columns through CQL. So does this mean that in CQL 3 an explicit schema is absolutely mandatory? It's now impossible

Re: ColumnFamilyInputFormat - error when column name is UUID

Answering myself: it seems we can't have any non type 1 UUIDs in column names. I used the UTF8 comparator and saved my UUIDs as strings, it worked. 2012/10/29 Marcelo Elias Del Valle > Hello, > > I am using ColumnFamilyInputFormat the same way it's described in this > example: > https://gith

Re: ColumnFamilyInputFormat - error when column name is UUID

Marcelo, das vezes q tive este problema geralmente era porque o valor UUID sendo tratado para o cassandra não correspondia a um valor "exato" em UUID, para isso utilizava bastante o UUID.randomUUID() (para gerar um UUID valido) e UUID.fromString("081f4500-047e-401c-8c0b-a41fefd099d7") - este para

Re: ColumnFamilyInputFormat - error when column name is UUID

Hmm, this brings the question of what uuid libraries are others using? I know this one generates type 1 UUIDs with two longs so it is 16 bytes. http://johannburkard.de/software/uuid/ Thanks, Dean From: Marcelo Elias Del Valle mailto:mvall...@gmail.com>> Reply-To: "user@cassandra.apache.org

Re: Simulating a failed node

Thanks, extremely helpful. The key bit was I wasn't flushing the old Keyspace before re-running the stress test, so I was stuck at RF = 1 from a previous run despite passing RF = 2 to the stress tool. On Sun, Oct 28, 2012 at 2:49 AM, Peter Schuller wrote: > > Operation [158320] retried 10 times

Re: ColumnFamilyInputFormat - error when column name is UUID

Dean, Are type 1 UUIDs the best ones to use if I want to avoid conflict? I saw this page: http://en.wikipedia.org/wiki/Universally_unique_identifier The only problem with type 1 UUIDs is they are "not opaque"? I know there is one kind of UUID that can generate two equal values if you gen

Re: ColumnFamilyInputFormat - error when column name is UUID

Err... Guess you replied in portuguese to the list :D 2012/10/29 Andre Tavares > Marcelo, > > das vezes q tive este problema geralmente era porque o valor UUID sendo > tratado para o cassandra não correspondia a um valor "exato" em UUID, para > isso utilizava bastante o UUID.randomUUID() (para

Re: Benifits by adding nodes to the cluster

This is how cassandra scales. More nodes means better performance. thank you, Andrey On Mon, Oct 29, 2012 at 2:57 PM, Roshan wrote: > Hi All > > This may be a silly question, but what kind of benefits we can get by adding > new nodes to the cluster? > > Some may be high availability. Any other

RE: Hinted Handoff runs every ten minutes

I'm running 1.1.5; the bug says it's fixed in 1.0.9/1.1.0. How can I check to see why it keeps running HintedHandoff? Steve -Original Message- From: Brandon Williams [mailto:dri...@gmail.com] Sent: Wednesday, October 24, 2012 4:56 AM To: user@cassandra.apache.org Subject: Re: Hinted

Re: Hinted Handoff runs every ten minutes

Dne 29.10.2012 23:24, Stephen Pierce napsal(a): I'm running 1.1.5; the bug says it's fixed in 1.0.9/1.1.0. How can I check to see why it keeps running HintedHandoff? you have tombstone is system.HintsColumnFamily use list command in cassandra-cli to check

idea drive layout - 4 drives + RAID question

For a server with 4 drive slots only, I'm thinking: either: - OS (1 drive) - Commit Log (1 drive) - Data (2 drives, software raid 0) vs - OS + Data (3 drives, software raid 0) - Commit Log (1 drive) or something else? also, if I can spare the wasted storage, would RAID 10 for cassandra data

Re: compression

> Any clue how to avoid it? Not really sure what went wrong. Diagnosing that sort of problem usually takes access to the running node and time to poke around and see what it does in responses to various things. Rebooting works for Windows 95 and Cassandra is not that different. Cheers

Re: idea drive layout - 4 drives + RAID question

I'm not sure whether the raid 0 gets you anything other than headaches should one of the drives fail. You can already distribute the individual Cassandra column families on different drives by just setting up symlinks to the individual folders. 2012/10/30 Ran User : > For a server with 4 drive slo

Re: CQL3: Unknown property 'comparator'?

More background http://www.datastax.com/dev/blog/thrift-to-cql3 > So does this mean that in CQL 3 an explicit schema is absolutely > mandatory? Not really, it sort of depends on your view. Lets say this is a "schema free" CF definition in CLI create column family clicks with key_validatio

Re: idea drive layout - 4 drives + RAID question

I was hoping to achieve approx. 2x IO (write and read) performance via RAID 0 (by accepting a higher MTBF). Do believe the performance gains of RAID0 are much lower and/or are not worth it vs the increased server failure rate? >From my understanding, RAID 10 would achieve the read performance ben

Re: idea drive layout - 4 drives + RAID question

I would generally recommend 1 drive for OS and commit log and 3 drive raid 0 for data. The raid does give you good performance benefit, and it can be convenient to have the OS on a side drive for configuration ease and better MTBF. -Tupshin On Oct 29, 2012 8:56 PM, "Ran User" wrote: > I was hopi

Re: idea drive layout - 4 drives + RAID question

Have you considered running RAID 10 for the data drives to improve MTBF? On one hand Cassandra is handling redundancy issues, on the other hand, reducing the frequency of dealing with failed nodes is attractive if cheap (switching RAID levels to 10). We have no experience with software RAID (have

Throughput decreases as latency increases with YCSB

Hi, I'm currently benchmarking Cassandra and have encountered some interesting behavior. As I increase the number of client threads (and connections), latency increases as expected but, at some point, throughput actually decreases. I've seen a few posts about this online, with no clear resolution

Re: Throughput decreases as latency increases with YCSB

> > I'm using YCSB on EC2 with one m1.large instance to drive client load To add, I don't believe this is due to YCSB. I've done a fair bit of client-side profiling and neither client CPU or NIC (or server NIC) are bottlenecks. I'll also add that this dataset fits in memory. Thanks! Peter