Amazon SimpleDB, Google Megastore & CAP
Nati Shalom (Gigaspaces) pulls out a couple of references from James Hamilton’s posts[1] on Amazon SimpleDB and Google Megastore consistency model concluding:
It is interesting to see that the reality is that even Google and Amazon - which I would consider the extreme cases for big data - realized the limitation behind eventual consistency and came up with models that can deal with scaling without forcing a compromise on consistency as I also noted in one of my recent NoCAP series
But he lefts out small details like these:
Update rates within a entity group are seriously limited by:
- When there is log contention, one wins and the rest fail and must be retried
- Paxos only accepts a very limited update rate (order 10^2 updates per second)
and
Cross entity group updates are supported by:
- two-phase commit with the fragility that it brings
- queueing ans asynchronously applying the changes
Original title and link: Amazon SimpleDB, Google Megastore & CAP (NoSQL databases © myNoSQL)
