<antirez>

There is a new DB option out there, I know it took a long time to be developed. While I don't know very well how it works I hope it will be an interesting player in the database landscape.

My initial feeling is that it will compete closely with Riak and MongoDB (the system seems more similar to MongoDB itself, but if it can scale well multi-nodes people that don't need high write availability may pick an immediate consistent database such as RethinkDB instead of Riak for certain applications).

While I consider the Amazon Dynamo design, and its original paper, one of the most interesting things produced in the field of databases in recent times, in the Redis world eventual consistency was never particularly discussed.

Redis Cluster for instance is a system biased towards consistency than availability. Redis Sentinel itself is an HA solution with the dogma of consistency and master slave setups.

This bias for consistent systems over more available but eventual consistent systems has some good reasons indeed, that I can probably reduce to three main points:

You can follow the commits in the next days in the "psync" branch at github:

https://github.com/antirez/redis/commits/psync

From an HN comment[1]

"(Geek note: In the late nineties I worked briefly with a D&D fanatic ops team lead. He threw a D100 when he came in every morning. Anything >90 he picked a random machine to failover 'politely'. If he threw a 100 he went to the machine room and switched something off or unplugged something. A human chaos monkey)."

[1] http://news.ycombinator.com/item?id=4736220

I'm pretty surprised no one tried to write a wrapper for redis-rb or other clients implementing a Dynamo-style system on top of Redis primitives.

Basically something like that:

1) You have a list of N Redis nodes.
2) On write, use consistent hashing and write the same thing to M nodes (M configurable).
3) On reads, read from M nodes and pick the most common reply to return to the client. For all the non-matching replies, use DUMP / RESTORE in Redis 2.6 to update the value of nodes that are in the minority.

I'm proud to be mentioned in this well-thought and non-bigot post: http://www.nerdess.net/waffling/why-it-awesome-be-girl-tech/

Also in perfect accordance with the hacking culture, the post is sort of an HOWTO for girls that want to be involved in IT.

In this busy days I had the idea to focus on a single, non-huge, self contained project for some time, that could allow me to work focused as much as hours as possible, and could provide a significant advantage to the Redis community.

It turns out, the best bet was partial replication resync. An always wanted feature that consists in the ability to a slave to resynchronize to a master without the need of a full resync (and RDB dump creation on the master side) if the replication link was interrupted for a short time, because of a timeout, or a network issue, or similar transient issue.

I love Github issues, it is one of the awesome things at Github IMHO: as simple as possible but actually under the hood pretty full featured.

However one of the things I love more is labels. It is a truly powerful thing to organize issues in a project-specific way. Unfortunately if an issue is a pull request, no labels can be attached. I wonder why.

Also I would love the ability to merge against multiple branches instead of the taget one, directly from the web UI.

I assume you already read the AWS report[1] about recent troubles. I think it is a very good argument you could use at work against design complexity and in favor of designing stuff that are at a complexity level where analysis of failure modes and prevention is actually possible.

[1] https://aws.amazon.com/message/680342/