Rename is_go_device variable to low_ram_device to better reflect its meaning and relation to ro.config.low_ram variable. Bug: 77299493 Bug: 75322373 Change-Id: I6e2eaebe79cf2e6edf861f7c602e52a5b573ad0a Merged-In: I6e2eaebe79cf2e6edf861f7c602e52a5b573ad0a Signed-off-by: Suren Baghdasaryan <surenb@google.com> (cherry picked from commit fe2be6cc44073b7ef09ca849004e5072bdf18857) |
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| tests | ||
| Android.bp | ||
| OWNERS | ||
| README.md | ||
| liblmkd_utils.c | ||
| lmkd.c | ||
| lmkd.rc | ||
| statslog.c | ||
| statslog.h | ||
README.md
Android Low Memory Killer Daemon
Introduction
Android Low Memory Killer Daemon (lmkd) is a process monitoring memory state of a running Android system and reacting to high memory pressure by killing the least essential process(es) to keep system performing at acceptable levels.
Background
Historically on Android systems memory monitoring and killing of non-essential processes was handled by a kernel lowmemorykiller driver. Since Linux Kernel 4.12 the lowmemorykiller driver has been removed and instead userspace lmkd daemon performs these tasks.
Android Properties
lmkd can be configured on a particular system using the following Android properties:
ro.config.low_ram: choose between low-memory vs high-performance device. Default = false.
ro.lmk.low: min oom_adj score for processes eligible to be killed at low vmpressure level. Default = 1001 (disabled)
ro.lmk.medium: min oom_adj score for processes eligible to be killed at medium vmpressure level. Default = 800 (non-essential processes)
ro.lmk.critical: min oom_adj score for processes eligible to be killed at critical vmpressure level. Default = 0 (all processes)
ro.lmk.critical_upgrade: enables upgrade to critical level. Default = false
ro.lmk.upgrade_pressure: max mem_pressure at which level will be upgraded because system is swapping too much. Default = 100 (disabled)
ro.lmk.downgrade_pressure: min mem_pressure at which vmpressure event will be ignored because enough free memory is still available. Default = 100 (disabled)
ro.lmk.kill_heaviest_task: kill heaviest eligible task (best decision) vs. any eligible task (fast decision). Default = false
ro.lmk.kill_timeout_ms: duration in ms after a kill when no additional kill will be done, Default = 0 (disabled)
ro.lmk.debug: enable lmkd debug logs, Default = false