Re:Show HN: Simperium, a realtime data layer
by andy_gayton on Thursday May 10, 2012 @11:25AM
(#3953992)
Important question saurik! Our primary store is mongo. All data is replicated in different availability zones and at least one additional replica which is kept in a different ec2 region. A running snapshot backup is also taken at least every 30 minutes. Simperium isn't a messaging service. Every change is persisted and versioned. So for the Simplesmash demo, you could have a slider that would allow you to go back in time and replay movements. A note on versions: they are stored in an RRD like fashion. At first every version is kept, and as they accumulate; older versions are compacted and become less granular. We plan on making what level of granularity is kept an adjustable option in the future.
When storing data in services provided and managed by other companies, it becomes more difficult to be certain that the risk tradeoffs are reasonable, as I'm in essence trusting that you aren't just storing the data on a single server in RAM on memcache or something ;P. Some more details would thereby be much appreciated.
(I understand, btw, that I can also have a server keeping a mirror of all of my data, which is definitely awesome, but I also would then want to get a better understanding of whether I would be a fool not to be doing that, or whether I can feel comfortable with having data stored on your servers ;P.)