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Questions tagged [voldemort]

Voldemort is a distributed key-value storage system used by LinkedIn. The source code is available under the Apache 2.0 license.

Voldemort is a distributed key-value storage system used by LinkedIn. The source code is available under the Apache 2.0 license.

Its web site project-voldemort.com describes it like this:

  • Data is automatically replicated over multiple servers.
  • Data is automatically partitioned so each server contains only a subset of the total data
  • Provides tunable consistency (strict quorum or eventual consistency)
  • Server failure is handled transparently
  • Pluggable Storage Engines -- BDB-JE, MySQL, Read-Only
  • Pluggable serialization -- Protocol Buffers, Thrift, Avro and Java Serialization
  • Data items are versioned to maximize data integrity in failure scenarios without compromising availability of the system
  • Each node is independent of other nodes with no central point of failure or coordination
  • Good single node performance: you can expect 10-20k operations per second depending on the machines, the network, the disk system, and the data replication factor
  • Support for pluggable data placement strategies to support things like distribution across data centers that are geographically far apart.

It is used at LinkedIn by numerous critical services powering a large portion of the site.

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How does Voldemort compare to Cassandra?

How does Voldemort compare to Cassandra? I'm not talking about size of community and only want to hear from people who have actually used both. Especially I'm interested in: How they dynamically scale when adding and removing nodes Query…
yazz.com
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Distributed caching for large objects

I want to share a very large object e.g. in orders of megabytes or even several gigabytes, between a set of machines. The object will be written once but may be read many times. Maybe a naive approach is to use a ceneteralized storage like redis.…
Saeed Shahrivari
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voldemort vs. couchdb

I am trying to decide whether to use voldemort or couchdb for an upcoming healthcare project. I want a storage system that has high availability , fault tolerance, and can scale for the massive amounts of data being thrown at it. What is the…
py213py
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Is anyone outside of LinkedIn using Voldemort?

I have been trying to find out more about Voldemort but it doesn't seem to be used outside of LinkedIn. Has anyone actually used it for a real system?
yazz.com
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Maven repository with Voldemort jars

I'm looking for a public Maven repository that has the Voldemort libraries. Anyone?
Wilfred Springer
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Correct usage of Voldemort as key-value pair?

I am trying to understand, how can Voldermort be used? Say, I have this scenario: Since, Voldemort is a key-value pair. I need to fetch a value (say some text) on the basis of 3 parameters. So, what will be the key in this case? I cannot use 3 keys…
zengr
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Can anyone explain scenarios where Project Voldermort or similar key value stores are useful?

I can see myself using Project Voldermort to cache results from a Traditional RDBMS query. But in this case, it provides almost no major advantage over other (Java) caching system such as EHcache Jcache etc. Where else could I use Project…
user193116
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How to use Voldemort Server from inside JUnit?

I'm trying to use Voldemort from inside JUnit in a Maven project. While the following Code compiles, it doesn't execute successfully: @Before public void setUp() throws Exception { // Start Voldemort VoldemortConfig config =…
user1737246
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CouchDB, Project Voldemort, Cassandra in a Java project

I am just evaluating some noSQL solutions for a current project. The different systems which caught my attention are currently Apache Cassandra, CouchDB and Project Voldemort The last one is more on hold in my evaluation because they wrote It is…
disco crazy
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JSON Serializer for arbitrary HashMaps in Voldemort

I am trying to set up the configuration for Voldemort key-value store. Now, I'd like to be able to store arbitrary hashmaps in it, but I haven't found the way to do so (or if it is possible). According to the documentation I should use this…
Goran Jovic
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When does Project Voldemort's InconsistencyResolver kick in?

I'm working on an application that basically needs to store a Map> (well, it's much more complicated than that but that's the basic idea) and I plan to be doing a lot of Set strings = storeClient.get("some…
Jack Edmonds
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Deciding suitable key value store : Voldemort vs Cassandra vs Memcached vs Redis

I am using triple store database for one of my project (semantic search engine for healthcare) and it works pretty fine. I am considering on giving it a performance boost by using a layer of key value store above triple store. Triple store querying…
CRS
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How to get all key-value pairs at once from a voldemort store?

int maxThreads = 300; ClientConfig clientConfig = new ClientConfig(); clientConfig.setMaxThreads(maxThreads); clientConfig.setMaxConnectionsPerNode(maxThreads); clientConfig.setConnectionTimeout(500,…
Amit
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Voldemort Python Client problems

I'm having problems having Python clients connecting to multiple servers that I set up using voldemort. I'm using Python 2.6.1 and Voldemort 0.81. Specifically, if I have a two node cluster, I don't seem to have any problems connecting to the…
Drew Harbison
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In Voldemort, why does the hash ring only extend to 2^31-1?

On the project voldemort design page: http://project-voldemort.com/design.php It is stated that the hash ring covers the interval [0, 2^31-1]. Now, the interval [0, 2^31-1] represents 2^31 total numbers, and the largest number 2^31-1 is just 31 bits…
Peter Skirko
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