Function TEST

cachelib/allocator/tests/MemoryMonitorTest.cpp:27–58

constexpr size_t kGBytes = kMBytes * 1024;

TEST(MemoryMonitorTest, increasingRateLimiter) {
  RateLimiter rl(true /*detectIncrease*/);
  rl.setWindowSize(10 /*windowSize*/);
  size_t rssVal = 10 * kGBytes;                  // Start at 10GB
  size_t reclaimPerIter = 2 * kGBytes * 5 / 100; // 5% of upper-lower bounds
  while (rssVal < 30 * kGBytes) {
    rl.addValue(rssVal); // Growth by 1GB per poll period
    EXPECT_EQ(0, rl.throttle(reclaimPerIter));
    rssVal += kGBytes;
  }
  // Reclaiming is stopped for next 10 iterations, followed by gradual
  // increase in next 10 iterations to full unthrottled reclaim.
  for (int i = 0; i < 21; i++) {
    if (i < 10) {
      rssVal += 10 * kMBytes; // Next 10 steps growth stops
    }
    rl.addValue(rssVal);
    if (i == 20) {
      EXPECT_EQ(reclaimPerIter, rl.throttle(reclaimPerIter));
    } else if (i >= 10) {
      EXPECT_LT(0, rl.throttle(reclaimPerIter));
    } else {
      EXPECT_EQ(0, rl.throttle(reclaimPerIter));
    }
  }
  // While rss is dropping, reclaim is unthrottled
  for (int i = 0; i < 10; i++) {
    rssVal -= kGBytes;
    rl.addValue(rssVal);
    EXPECT_EQ(reclaimPerIter, rl.throttle(reclaimPerIter));
  }
}

TEST(MemoryMonitorTest, decreasingRateLimiter) {
  RateLimiter rl(false /*detectIncrease*/);