【转】Android: HowTo设置app不被系统kill掉

lowmemorykiller的操作规则比如为

write /sys/module/lowmemorykiller/parameters/adj 0,1,2,4,7,15

write /sys/module/lowmemorykiller/parameters/minfree 2048,3072,4096,6144,7168,8192

 

可以看到，设置persistent后， oom_adj=-12，永远没有机会被lowmemorykiller处理

 

android:persistent 
Whether or not the application should remain running at all times — "true" if it should, and "false" if not. The default value is "false". Applications should not normally set this flag; persistence mode is intended only for certain system applications

 

代码

ActivityManagerService.java
    final ProcessRecord addAppLocked(ApplicationInfo info) {
        ProcessRecord app = getProcessRecordLocked(info.processName, info.uid);

        if (app == null) {
            app = newProcessRecordLocked(null, info, null);
            mProcessNames.put(info.processName, info.uid, app);
            updateLruProcessLocked(app, true, true);
        }

        if ((info.flags&(ApplicationInfo.FLAG_SYSTEM|ApplicationInfo.FLAG_PERSISTENT))
                == (ApplicationInfo.FLAG_SYSTEM|ApplicationInfo.FLAG_PERSISTENT)) {
            app.persistent = true;
            app.maxAdj = CORE_SERVER_ADJ;
        }
        if (app.thread == null && mPersistentStartingProcesses.indexOf(app) < 0) {
            mPersistentStartingProcesses.add(app);
            startProcessLocked(app, "added application", app.processName);
        }

        return app;
    }

可以看到同时符合FLAG_SYSTEM(/system/app目录)及FLAG_PERSISTENT(android:persistent="true")

的app，设置app.maxAdj = CORE_SERVER_ADJ(-12)，而adj=-12不会被lowmemorykiller处理