There are two sets of statistics related to MemDB data striping: MemDB statistics and striping-statistics.

MemDB statistics and striping

MemDB collects statistics under the MemDB-Replicated and MemDB-Local parameter sets, within each data stripe. They can be monitored on a per-stripe basis, or viewed as an aggregate across all stripes.

The parameter set names of the per-stripe statistics end with suffix of the form .stripe-N. For example, the stats for the first stripe will have suffix .stripe-0.

Striping statistics

MemDB maintains atomicity, consistency and isolation of data across stripes. This involves managing the versions of data exposed to various client transactions. The MemDB-Timestamp parameter set contains the relevant statistics.

This is a listing of the statistics available for a particular MemDB instance, within the MemDB-Timestamp parameter set:

Counter type statistics:
Id: Name:             Label:     Description:
0   waitingThreads    waiting    The number of threads waiting for a timestamp to become safe
1   unexposedCommits  unexposed  The number of commits which are not yet safe to expose

A database transaction containing at least one write is considered "safe to expose to client transactions" when (as shown by these statistics) all its changes — as well as all the write transactions that precede them — are available across all stripes.

Note These statistics are expected to have low values even under load (often with value zero), and should stay at zero when Rhino is not under load.
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Rhino Version 3.2