Re: LMDB persistent snapshots

[Michael Conrad <mike@nrdvana.net>]

On 07/10/2017 12:16 PM, Howard Chu wrote:
> Michael Conrad wrote:
> > Hi, I'm scoping out my options for databases that support 
> > snapshotting.  From what I've read so far, this is a natural feature 
> > of LMDB,
>
> Not really. The persistent state only records the 2 most recent 
> transactions. 

Hm, well so much for that idea ;-)   But could you clarify what would 
happen in a scenario like:

Proc1: Begin Read Transaction t1
Proc2: Write Transaction t2
Proc2: Write transaction t3
Proc3: Begin Read Transaction t4
Proc2: Write Transaction t5
Proc2: Write Transaction t6

After those steps, are process 1 and process 3 still able to continue 
reading their data, and is all the data they see consistent with the 
state of the database at the time they began the transaction?

Thanks,
-Mike