Monitoring

ConsumedReadCapacityUnits / ConsumedWriteCapacityUnits:
    statistic 用 Sum
    含义是这个 Period 内总共消耗了多少 capacity units

ProvisionedReadCapacityUnits / ProvisionedWriteCapacityUnits:
    statistic 用 Average
    含义是这个 Period 内平均配置了多少 capacity units per second

capacity usage percent: consumed_sum / (provisioned_average * period_seconds) * 100

example:
    period = 300s
    ConsumedReadCapacityUnits Sum = 18000
    ProvisionedReadCapacityUnits Average = 100
    usage = 18000 / (100 * 300) * 100 = 60%

on-demand 没有 ProvisionedReadCapacityUnits / ProvisionedWriteCapacityUnits 这个固定分母。

监控重点:
    ThrottledRequests
    ReadAccountLimitThrottleEvents / WriteAccountLimitThrottleEvents
    ReadMaxOnDemandThroughputThrottleEvents / WriteMaxOnDemandThroughputThrottleEvents
    ConsumedReadCapacityUnits / ConsumedWriteCapacityUnits trend