Flush error with a specific metric

[gpereraDX]

I have configured collectd with aerospike plugin and CW plugin. First tests, i just included into whitelist configs the metrics this way: aerospike-.* and all metrics loaded fine.

Once i wanted to select specific metrics, my current desired setup is:

aerospike.*cluster_clock_skew_stop_writes_sec
aerospike.*cluster_size
aerospike.*dead_partitions
aerospike.*device_available_pct
aerospike.*hwm_breached
aerospike.*stop_writes
aerospike.*unavailable_partitions
aerospike.*xdr_timelag
aerospike.*memory_free_pct

But i obtain the following error:

[error] [AmazonCloudWatchPlugin][cloudwatch.modules.flusher] _flush error:   Original map size: 10

if i remove the last metric aerospike.*memory_free_pct the error wont come up. Im not sure why this is happening.

UPDATE: So after doing some debugging/testing, i found out that the error pops for 9 metrics. If i add another metric to the whitelist config file, the error would stop popping. So i believe there is some weird edge case going on regarding amount of metrics.