windows_exporter/internal/collector/time/AGENTS.md

time collector

The collector reads the single-instance PDH object Windows Time Service with pdh.CounterTypeRaw. The object needs the W32Time service. These notes were recorded on Windows Server 2025 (build 26100), a domain controller and Hyper-V guest.

• Computed Time Offset (PERF_COUNTER_LARGE_RAWCOUNT) and NTP Roundtrip Delay (PERF_COUNTER_RAWCOUNT) are gauges in microseconds, per the help text. The offset is absolute, so it is never negative.
• Clock Frequency Adjustment is a gauge in nominal clock units; Clock Frequency Adjustment (PPB) is the same adjustment in parts per billion. In the sample they were 0 and 600.
• The struct tag spells the counter Clock Frequency Adjustment (ppb), but Windows names it (PPB). The name lookup is case-insensitive, and the counter was read on this host.
• NTP Server Incoming Requests and NTP Server Outgoing Responses are PERF_COUNTER_BULK_COUNT; the raw value is a cumulative count.
• NTP Client Time Source Count, NTP Roundtrip Delay and both NTP server counters were 0 on this host.

Counter reference

Recorded on Windows Server 2025 (build 26100). Raw and Base are the first and second values that pdh.CounterTypeRaw returns for the sample instance.

Windows Time Service

Single-instance.

Counters the collector reads:

Counter	Type	Raw	Base
Clock Frequency Adjustment	PERF_COUNTER_RAWCOUNT	0
Clock Frequency Adjustment (PPB)	PERF_COUNTER_RAWCOUNT	600
Computed Time Offset	PERF_COUNTER_LARGE_RAWCOUNT	83
NTP Client Time Source Count	PERF_COUNTER_RAWCOUNT	0
NTP Roundtrip Delay	PERF_COUNTER_RAWCOUNT	0
NTP Server Incoming Requests	PERF_COUNTER_BULK_COUNT	0
NTP Server Outgoing Responses	PERF_COUNTER_BULK_COUNT	0