High Capacity Counters

What are High Capacity Counters?

Since the advent of faster and faster network interfaces, SNMP’s original use of 32 bits for counters has become somewhat outdated. As a counter of network throughput in bytes, a 32-bit counter can only count up to approximately 4GB before rolling back to zero. On a very fast interface, the counter may reset before it can even be read again.

High Capacity Counters solve this issue by increasing counters from 32-bit (maximum of 4,294,967,295 bytes) to 64-bit (maximum of 9,223,372,036,854,775,807 bytes).

How does PeakHour use them?

If PeakHour detects that your device supports High Capacity (64-bit) counters, it will automatically use them to measure throughput. This results in more accurate usage tracking, especially while your Mac is asleep or switched off.

PeakHour indicates whether it has detected 64-bit counters in the monitor’s settings (Settings → Monitors, select the monitor) under Device → 64-bit Counters:

For more information on why High Capacity Counters matter for usage accuracy, see Usage Monitoring. The counter objects themselves are defined in RFC 2863 — The Interfaces Group MIB.