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I know this is HN and people love to troll, but it makes me sad when I see you using falsehoods to take a steaming dump on a group of engineers that are obsesse

by pmcf 4y ago

I know this is HN and people love to troll, but it makes me sad when I see you using falsehoods to take a steaming dump on a group of engineers that are obsessed with building a database that can scale while maintaining the highest level of correctness possible. All in Open Source... for free! Spend some time on the Cassandra mailing list and you'll walk away feeling much differently. Instead of complaining, participate. Some examples of the project's obsession with quality and correctness: https://cassandra.apache.org/_/blog/The-Path-to-Green-CI.html https://cassandra.apache.org/_/blog/The-Path-to-Green-CI.htm... https://cassandra.apache.org/_/blog/Finding-Bugs-in-Cassandra's-Internals-with-Property-based-Testing.html https://cassandra.apache.org/_/blog/Finding-Bugs-in-Cassandr... https://cassandra.apache.org/_/blog/Testing-Apache-Cassandra-4.html https://cassandra.apache.org/_/blog/Testing-Apache-Cassandra... https://cassandra.apache.org/_/blog/Introducing-Apache-Cassandra-4-Beta-Battle-Tested-From-Day-One.html https://cassandra.apache.org/_/blog/Introducing-Apache-Cassa...

skyde 4y ago
sorry to disappoint you but there is a reason Cassandra tried to add LWT using paxos. it mostly work but it’s extremely slow and still have many bugs. https://www.datastax.com/blog/lightweight-transactions-cassandra-20 https://www.datastax.com/blog/lightweight-transactions-cassa...
- _benedict 4y ago
  LWTs were added for a very simple reason: stronger isolation where the performance trade-off makes sense. Nothing to do with the GP comment. Until recently they were indeed slow over the WAN, and they remain slow under heavy contention. They are now faster than peer features for WAN reads. However, the claim that they have many bugs needs to be backed up. I just finished overhauling Paxos in Cassandra and it is now one of the most thoroughly tested distributed consensus implementations around.
  - skyde 4y ago
    LWT is still the only way to guarantee your write don’t random disappear and that conditional update are really conditional. LWT still have awful performance compared to a write request with same guarantee in any other database.
- pmcf 4y ago
  That blog was posted 9 years ago. Needless to say, a lot of improvement and engineering has happened since then. The limited use cases of LWTs will soon be replaced with general, ACID transactions. https://thenewstack.io/an-apache-cassandra-breakthrough-acid-transactions-at-scale/ https://thenewstack.io/an-apache-cassandra-breakthrough-acid...
  - skyde 4y ago
    This new « accord » thing look very promising! If this get merged into Cassandra this change everything! A prototype has been developed that has demonstrated its correctness against Jepsen.io’s Maelstrom tool

by pmcf 4y ago

skyde 4y ago

sorry to disappoint you but there is a reason Cassandra tried to add LWT using paxos. it mostly work but it’s extremely slow and still have many bugs. https://www.datastax.com/blog/lightweight-transactions-cassandra-20 https://www.datastax.com/blog/lightweight-transactions-cassa...

_benedict 4y ago
LWTs were added for a very simple reason: stronger isolation where the performance trade-off makes sense. Nothing to do with the GP comment. Until recently they were indeed slow over the WAN, and they remain slow under heavy contention. They are now faster than peer features for WAN reads. However, the claim that they have many bugs needs to be backed up. I just finished overhauling Paxos in Cassandra and it is now one of the most thoroughly tested distributed consensus implementations around.
- skyde 4y ago
  LWT is still the only way to guarantee your write don’t random disappear and that conditional update are really conditional. LWT still have awful performance compared to a write request with same guarantee in any other database.
pmcf 4y ago
That blog was posted 9 years ago. Needless to say, a lot of improvement and engineering has happened since then. The limited use cases of LWTs will soon be replaced with general, ACID transactions. https://thenewstack.io/an-apache-cassandra-breakthrough-acid-transactions-at-scale/ https://thenewstack.io/an-apache-cassandra-breakthrough-acid...
- skyde 4y ago
  This new « accord » thing look very promising! If this get merged into Cassandra this change everything! A prototype has been developed that has demonstrated its correctness against Jepsen.io’s Maelstrom tool