Merge "psi: avoid divide-by-zero crash inside virtual machines" (da061aae) · Commits · e / devices / android_kernel_xiaomi_nabu

Documentation/accounting/psi.txt

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		@@ -62,3 +62,12 @@ well as medium and long term trends. The total absolute stall time is
		tracked and exported as well, to allow detection of latency spikes
		which wouldn't necessarily make a dent in the time averages, or to
		average trends over custom time frames.

		Cgroup2 interface
		=================

		In a system with a CONFIG_CGROUP=y kernel and the cgroup2 filesystem
		mounted, pressure stall information is also tracked for tasks grouped
		into cgroups. Each subdirectory in the cgroupfs mountpoint contains
		cpu.pressure, memory.pressure, and io.pressure files; the format is
		the same as the /proc/pressure/ files.

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		@@ -966,6 +966,12 @@ All time durations are in microseconds.
		$PERIOD duration. "max" for $MAX indicates no limit. If only
		one number is written, $MAX is updated.

		cpu.pressure
		A read-only nested-key file which exists on non-root cgroups.

		Shows pressure stall information for CPU. See
		Documentation/accounting/psi.txt for details.


		Memory
		------
		@@ -1271,6 +1277,12 @@ PAGE_SIZE multiple when read back.
		higher than the limit for an extended period of time. This
		reduces the impact on the workload and memory management.

		memory.pressure
		A read-only nested-key file which exists on non-root cgroups.

		Shows pressure stall information for memory. See
		Documentation/accounting/psi.txt for details.


		Usage Guidelines
		~~~~~~~~~~~~~~~~
		@@ -1408,6 +1420,12 @@ IO Interface Files

		8:16 rbps=2097152 wbps=max riops=max wiops=max

		io.pressure
		A read-only nested-key file which exists on non-root cgroups.

		Shows pressure stall information for IO. See
		Documentation/accounting/psi.txt for details.


		Writeback
		~~~~~~~~~

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		@@ -3490,6 +3490,10 @@
		before loading.
		See Documentation/blockdev/ramdisk.txt.

		psi= [KNL] Enable or disable pressure stall information
		tracking.
		Format: <bool>

		psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
		probe for; one of (bare\|imps\|exps\|lifebook\|any).
		psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports

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