tree 76ee6f105e0336370f1e999569059030b505d370
parent fa667edb56bb58603f6e044df987287c1e1c47ba
author Martin Liu <liumartin@google.com> 1597345882 +0800
committer Martin Liu <liumartin@google.com> 1597379388 +0000

lmkd: Add a margin for watermark when swap free is low

When swap is depleted file cache thrashing might result in allocations
quickly pushing memory below low watermark and kswapd quickly pushing
it back above high watermark. In this situation free memory stays above
high watermark most of the time and lmkd during its periodic wake-ups
has low chance of detecting low memory conditions. Add a 15% margin
for high watermark which would allow lmkd to kill if swap is low,some
memory was reclaimed since the last wakeup and free memory is just
above the high watermark limit.

Bug: 163134367
Test: heavy loading launch
Signed-off-by: Martin Liu <liumartin@google.com>
Change-Id: I5694736b04bafcd13c01f4b51e242e2ac4ff55a8