| commit | 08bfa985d133859b5d0f03a399fc6510c839a80e | [log] [tgz] |
|---|---|---|
| author | Suren Baghdasaryan <surenb@google.com> | Thu Jul 26 16:34:27 2018 -0700 |
| committer | Suren Baghdasaryan <surenb@google.com> | Fri Aug 10 14:21:31 2018 -0700 |
| tree | 829894ae73b76e511490c74006ffa6b783f50329 | |
| parent | 2f81a77326103493492ff416057f1c0ee4b99039 [diff] |
lmkd: Add meminfo logging after each kill for easy troubleshooting While troubleshooting memory pressure related issues it's hard to get a good view of the memory state when lmkd kill happens. Logging relevant information from /proc/meminfo file that was used to make a kill decision is very helpful for further analysis. To do this efficiently we are using Android Logger event library functions and log the data used for kill decision after the kill signal was issued. Test: Run lmkd_unit_test and logcat -b events -v descriptive Change-Id: Id5de41b9d91a04dd5d3eb9b85d4e1babe9755628 Signed-off-by: Suren Baghdasaryan <surenb@google.com>
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.
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.
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.use_minfree_levels: use free memory and file cache thresholds for making decisions when to kill. This mode works the same way kernel lowmemorykiller driver used to work. 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