RethinkDB 2.1 is out: high availability • Hacker News Board

Re: RethinkDB 2.1 is out: high availability

#61

Post by WaltPurvis » Tue, Aug 11, 2015, 9:51 PM UTC

jchrisa wrote: post #33

mikegioia wrote: post #23

Earlier quoted context omitted.

That's funny, I just installed that over the weekend and was testing it out. It's really good but what sort of through me off was the high $/node licensing fee if you want the Enterprise edition. It basically starts at $5k/year/node and that's just too oppressive. Do you use the Community Edition and if so is it generally stable / suits your needs? I didn't read your article but I'll check it out tonight.

I'm a cofounder of Couchbase. Almost all our code is Apache 2.0, and we make the Community builds available for everyone. Enterprise builds are free to use for a small test cluster. Unless you are a business where $5k/node looks reasonable to pay for peace of mind, you are probably fine with the Community Edition. A lot of the customers paying for Enterprise Edition are moving to Couchbase from Oracle, so they are pa…

As far as I can tell the Community Edition lags far behind the Enterprise Edition in stability and improvements. The latest available Community Edition is v3.0.1, released in October 2014. Since then, there has been a v3.0.2 edition released in December 2014, and a v3.0.3 released in March 2015, both of which had "critical bug fixes" according to the release notes, plus a new version, 3.1.0, released in July 2015. None of these post-3.0.1 versions are available as a Community Edition, they're only available to Enterprise customers -- is that correct?

The Couchbase web site says: "Bug fixes and new features are eventually integrated with the Community Edition (CE), but this typically takes several weeks." But from what I can tell it's not "several weeks" -- it's at least 10 months.

Am I misunderstanding something?

Re: RethinkDB 2.1 is out: high availability

#62

Post by coffeemug » Tue, Aug 11, 2015, 9:56 PM UTC

teraflop wrote: post #50

coffeemug wrote: post #32

Earlier quoted context omitted.

> Leader needs to send AppendEntries and slave needs to apply to persistent storage and ACK. Leader needs to wait for majority of ACKS before responding to the client. That's the same as your three-node replication scenario, so what am I missing here? A couple of things -- the payload in Raft tends to be much higher (though it could probably be fixed with sufficient engineering effort), and in some scenarios this pro…

The parent comment asked: > Does Rethink db relax consistency guarantees in some cases to achieve better latency? You responded: > RethinkDB doesn't relax consistency guarantees; we implement them in a different way. But the page you linked says: > `single` returns values that are in memory (but not necessarily written to disk) on the primary replica. This is the default. > `majority` will only return values that are…

Sorry, this is a bit nuanced and my comment was unclear.

We implement a variety of modes for reading and writing that allow the user to select different trade-offs for consistency and performance. By default: writes are always safe; reads are safe when the cluster is healthy, but can sometimes have anomalies in failure scenarios. You can also do `majority` reads which are completely safe even during failure scenarios, but are slower.

However note, that the default read mode isn't an "anything can happen" implementation. The guarantees are precisely defined, and 2.1 passes all tests in a large variety of failure scenarios with respect to these guarantees.

My comment about not relaxing consistency guarantees was meant in a slightly different context. The OP was talking write transactions (and implementing individual writes with Raft vs. using a different way), and I pointed out that we don't relax consistency guarantees for writes despite not using Raft.

I realize my comment was confusing -- sorry about that; I didn't mean to mislead.

Re: RethinkDB 2.1 is out: high availability

#63

Post by mglukhovsky » Tue, Aug 11, 2015, 9:58 PM UTC

juijasmem wrote: post #57

Can I ask please why you don't provide ready to use, fine tunned amazon images? This is preventing me to use it now as I cannot find reliable configuration or information. Also the current image is out of date. Thanks

Amazon changed the image format, and we've been working to update our images to use it. Here's some more detail: https://github.com/rethinkdb/marketplace-ami/issues/1

If you like, you can launch a 1.16 AMI, ssh into the instance, and run `apt-get update && apt-get install rethinkdb` to update to RethinkDB 2.1.

Thanks for being patient -- we'll get the official images updated soon.

Re: RethinkDB 2.1 is out: high availability

#64

Post by coffeemug » Tue, Aug 11, 2015, 9:59 PM UTC

fweespeech wrote: post #58

coffeemug wrote: post #2

Slava @ RethinkDB here. I'll be around all day to answer questions about the release (along with a few other engineers on our team). We're very excited about this release -- it makes the lives of RethinkDB users dramatically better because they won't have to wake up anymore in the middle of the night in case of most hardware failures :) It also took over a year to build and test, and has been one of the most challeng…

How is the WAN replication performance for a cluster in 3 DCs with ~100-200ms RTT? Or is WAN replication performance on the todo list?

WAN replication works out of the box, and RethinkDB was designed with multidatacenter setups in mind. Feel free to email me at slava@rethinkdb.com if you need to discuss a specific use case.

Re: RethinkDB 2.1 is out: high availability

#65

Post by danielmewes » Tue, Aug 11, 2015, 10:12 PM UTC

teraflop wrote: post #54

coffeemug wrote: post #51

Earlier quoted context omitted.

AFAIK the tests account for that and test different scenarios (i.e. not all unsafe modes are created equal; a product can still fail the relevant test cases in fast-but-unsafe mode). We pass the fast-but-unsafe tests (i.e. we fulfill the guarantees you'd expect in that mode), and also pass the stricter guarantees in the slow-but-safe mode. However you're right that we don't pass stricter guarantees in fast-but-unsafe…

Good to know. The test code in that pull request only tests the case where read_mode="majority", so I'm looking forward to seeing the other scenarios when they become available.

We only submitted the configuration that passed all scenarios, but tested some of the others internally. You generally don't get guaranteed linearizability of operations under network partitions in any of the faster configurations.

Re: RethinkDB 2.1 is out: high availability

#66

Post by GordyMD » Tue, Aug 11, 2015, 10:43 PM UTC

So happy you've added in Math functions into ReQL. Thank you!

Re: RethinkDB 2.1 is out: high availability

#67

Post by kevinbowman » Tue, Aug 11, 2015, 10:44 PM UTC

coffeemug wrote: post #2

Slava @ RethinkDB here. I'll be around all day to answer questions about the release (along with a few other engineers on our team). We're very excited about this release -- it makes the lives of RethinkDB users dramatically better because they won't have to wake up anymore in the middle of the night in case of most hardware failures :) It also took over a year to build and test, and has been one of the most challeng…

Congrats on the release! Could you update the docker hub image? I'm impatient to try it...

Re: RethinkDB 2.1 is out: high availability

#68

Post by GordyMD » Tue, Aug 11, 2015, 10:46 PM UTC

coffeemug wrote: post #4

akbar501 wrote: post #3

@coffeemug, do you have an ETA on when performance benchmarks will be released?

This is totally my fault. I've had a pretty comprehensive benchmark report pdf sitting in my inbox for a few months now that the performance team put together, but something else always took my attention away. I'll ask the documentation team to format it and add it to the official documentation. Sorry this slipped through the cracks.

Really looking forward to seeing this.

Re: RethinkDB 2.1 is out: high availability

#69

Post by dantiberian » Tue, Aug 11, 2015, 10:55 PM UTC

RethinkDB is great and has a lot of great features, however the thing that has impressed me the most is the way they communicate with the community. They are incredibly responsive and friendly on GitHub and IRC. It's not uncommon to get a response to a bug report within an hour or two (not that they have any obligation to this). They're incredibly nice.

It looks like they try to follow http://www.defmacro.org/2013/04/03/issue-etiquette.html, it'd be great to see other companies adopt it too.

Thanks folks!

Re: RethinkDB 2.1 is out: high availability

#70

Post by hardwaresofton » Tue, Aug 11, 2015, 11:04 PM UTC

dantiberian wrote: post #69

RethinkDB is great and has a lot of great features, however the thing that has impressed me the most is the way they communicate with the community. They are incredibly responsive and friendly on GitHub and IRC. It's not uncommon to get a response to a bug report within an hour or two (not that they have any obligation to this). They're incredibly nice. It looks like they try to follow http://www.defmacro.org/2013/04…

+1 to this, visited the team (I happened to be in California) once with very very short notice, and the office was a small tight-knit nice group of people.