DO NOT MERGE: lmkd: retune rate at which processes are killed
Kill a single process at a time and try to wait up to 100ms for
that process to reclaim memory before triggering another kill.
Test: boots, works
bug: 116877958
Change-Id: I6775d0534b3e3728c04389d3eae1a00e3cbf9f27
(cherry picked from commit afb3a15f39e73978c071a58d3466993293c6d3b1)
diff --git a/lmkd/lmkd.c b/lmkd/lmkd.c
index bf265b0..6e29453 100644
--- a/lmkd/lmkd.c
+++ b/lmkd/lmkd.c
@@ -27,8 +27,8 @@
#include <sys/eventfd.h>
#include <sys/mman.h>
#include <sys/socket.h>
-#include <sys/types.h>
#include <sys/sysinfo.h>
+#include <sys/types.h>
#include <unistd.h>
#include <cutils/properties.h>
@@ -957,6 +957,8 @@
return maxprocp;
}
+static int last_killed_pid = -1;
+
/* Kill one process specified by procp. Returns the size of the process killed */
static int kill_one_process(struct proc* procp) {
int pid = procp->pid;
@@ -997,6 +999,8 @@
TRACE_KILL_END();
+ last_killed_pid = pid;
+
if (r) {
ALOGE("kill(%d): errno=%d", pid, errno);
return -1;
@@ -1135,6 +1139,22 @@
(to->tv_usec - from->tv_usec) / 1000;
}
+static bool is_kill_pending(void) {
+ char buf[24];
+ if (last_killed_pid < 0) {
+ return false;
+ }
+
+ snprintf(buf, sizeof(buf), "/proc/%d/", last_killed_pid);
+ if (access(buf, F_OK) == 0) {
+ return true;
+ }
+
+ // reset last killed PID because there's nothing pending
+ last_killed_pid = -1;
+ return false;
+}
+
static void mp_event_common(int data, uint32_t events __unused) {
int ret;
unsigned long long evcount;
@@ -1176,7 +1196,11 @@
gettimeofday(&curr_tm, NULL);
if (kill_timeout_ms) {
- if (get_time_diff_ms(&last_kill_tm, &curr_tm) < kill_timeout_ms) {
+ // If we're within the timeout, see if there's pending reclaim work
+ // from the last killed process. If there is (as evidenced by
+ // /proc/<pid> continuing to exist), skip killing for now.
+ if ((get_time_diff_ms(&last_kill_tm, &curr_tm) < kill_timeout_ms) &&
+ (low_ram_device || is_kill_pending())) {
kill_skip_count++;
return;
}
@@ -1313,7 +1337,7 @@
min_score_adj = level_oomadj[level];
}
- pages_freed = find_and_kill_processes(min_score_adj, pages_to_free);
+ pages_freed = find_and_kill_processes(min_score_adj, 0);
if (pages_freed == 0) {
/* Rate limit kill reports when nothing was reclaimed */
@@ -1321,10 +1345,8 @@
report_skip_count++;
return;
}
- }
-
- if (pages_freed >= pages_to_free) {
- /* Reset kill time only if reclaimed enough memory */
+ } else {
+ /* If we killed anything, update the last killed timestamp. */
last_kill_tm = curr_tm;
}
