docs/CONTROL_GROUP_INTERFACE.md: document accounting information available via D-Bus

diff --git a/docs/CONTROL_GROUP_INTERFACE.md b/docs/CONTROL_GROUP_INTERFACE.md
index f95cf7607b53b47d67353648ea3812f4f45f0e65..5298fa42c8a0a0c003b6e4cb15641736e4c41d10 100644 (file)
--- a/docs/CONTROL_GROUP_INTERFACE.md
+++ b/docs/CONTROL_GROUP_INTERFACE.md
@@ -223,7 +223,7 @@ Use these APIs to register any kind of process workload with systemd to be place
 
 ### Reading Accounting Information
 
-Note that there's currently no systemd API to retrieve accounting information from cgroups. For now, if you need to retrieve this information use `/proc/$PID/cgroup` to determine the cgroup path for your process in the `cpuacct` controller (or whichever controller matters to you), and then read the attributes directly from the cgroup tree.
+Accounting information is available via the `MemoryCurrent`, `MemoryPeak`, `MemorySwapCurrent`, `MemorySwapPeak`, `MemoryZSwapCurrent`, `MemoryAvailable`, `EffectiveMemoryMax`, `EffectiveMemoryHigh`, `CPUUsageNSec`, `EffectiveCPUs`, `EffectiveMemoryNodes`, `TasksCurrent`, `EffectiveTasksMax`, `IPIngressBytes`, `IPIngressPackets`, `IPEgressBytes`, `IPEgressPackets`, `IOReadBytes`, `IOReadOperations`, `IOWriteBytes`, and `IOWriteOperations` D-Bus properties.  To read this and other information directly from the cgroup tree, get the unit's cgroup path (relative to `/sys/fs/cgroup`) from the `ControlGroup` property, by calling [`sd_pid_get_cgroup()`](https://www.freedesktop.org/software/systemd/man/latest/sd_pid_get_cgroup.html), or by parsing `/proc/$PID/cgroup`.
 
 If you want to collect the exit status and other runtime parameters of your transient scope or service unit after the processes in them ended set the `RemainAfterExit` boolean property when creating it. This will has the effect that the unit will stay around even after all processes in it died, in the `SubState="exited"` state. Simply watch for state changes until this state is reached, then read the status details from the various properties you need, and finally terminate the unit via `StopUnit()` on the `Manager` object or `Stop()` on the `Unit` object itself.