Collision probability of ObjectId vs UUID in a large distributed system
Considering that an UUID rfc 4122 (16 bytes) is much larger than a MongoDB ObjectId (12 bytes), I am trying to find out how their collision probability compare.
I know that is something around quite unlikely, but in my case most ids will be generated within a large number of mobile clients, not within a limited set of servers. I wonder if in this case, there is a justified concern.
Compared to the normal case where all ids are generated by a small number of clients:
- It might take months to detect a collision since the document creation
- IDs are generated from a much larger client base
- Each client has a lower ID generation rate
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Which one is faster in terms of Performance used for benchmark I/O (RAW) Read/Write Vs ioctl in linux? why and How? Regards, Srinivasa Raghavan.
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How can I convert a .NET GUID to a MongoDB ObjectID (in C#). Also, can I convert it back again to the same GUID from the ObjectID?