I'm having an odd problem with incrementing counters simultaneously during a 
scan (both in separate processes).

For low rate counters, there is no problem (< 1 increment per second), but for 
the higher rate counters (>10 increments per second), there is an inconsistency 
in the counter values.

Averaging the values over time gives the correct count (i.e. the counter itself 
is still increasing correctly), but at certain samples the counter drops down 
to some seemingly random number.  This random number is consistent for about a 
day and a half then jumps to a different random number for the next day and a 
half - this cycle coincides exactly with compaction of the table in question.

Again, the counter value itself, when it is not equal to the random number of 
the day, is correct.  I'm wondering if there is something going on underneath 
that would cause
1) the incorrect but consistent number when incrementing and scanning 
simultaneously
2) the random number reset and its relationship with compaction of the table

Keep in mind that most of the hbase settings are at default.

Thanks!
p.s. I ran a smaller experiment using hbase shell, and found the counters to be 
consistent even for the high rate counters.  I am wondering if there is a 
buffering issue with the htable scanner object if it is unable to obtain a lock 
on the row it will default to the data on disk?

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