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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The PSI mechanism is useful tool to monitor pressure stall information in the system. Currently, the minimum window size is set to 500ms. May we know what is the rationale for this? For lightweight systems such as Linux Embedded Systems, PSI can be used to monitor and track memory pressure building up in the system and respond quickly to such memory demands. Example, the Linux Embedded Systems could be a secondary VM system which requests for memory from Primary host. With 500ms window size, the sampling period is 50ms (one-tenth of windwo size). So the minimum amount of time the process needs to stall, so that a PSI event can be generated and actions can be done is 50ms. This reaction time can be much reduced by reducing the sampling time (by reducing window size), so that responses to such memory pressures in system can be serviced much quicker. Please let us know your thoughts on reducing window size to 50ms. Sudarshan Rajagopalan (1): psi: reduce min window size to 50ms kernel/sched/psi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.7.4 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel