|
|
|
@ -542,14 +542,34 @@ int GetL0ThresholdSpeedupCompaction(int level0_file_num_compaction_trigger, |
|
|
|
|
// SanitizeOptions() ensures it.
|
|
|
|
|
assert(level0_file_num_compaction_trigger <= level0_slowdown_writes_trigger); |
|
|
|
|
|
|
|
|
|
if (level0_file_num_compaction_trigger < 0) { |
|
|
|
|
return std::numeric_limits<int>::max(); |
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
const int twice_level0_trigger = level0_file_num_compaction_trigger * 2; |
|
|
|
|
|
|
|
|
|
// overflow protection
|
|
|
|
|
if (twice_level0_trigger < 0) { |
|
|
|
|
return std::numeric_limits<int>::max(); |
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
// 1/4 of the way between L0 compaction trigger threshold and slowdown
|
|
|
|
|
// condition.
|
|
|
|
|
// Or twice as compaction trigger, if it is smaller.
|
|
|
|
|
return std::min(level0_file_num_compaction_trigger * 2, |
|
|
|
|
const int one_fourth_trigger_slowdown = |
|
|
|
|
level0_file_num_compaction_trigger + |
|
|
|
|
(level0_slowdown_writes_trigger - |
|
|
|
|
level0_file_num_compaction_trigger) / |
|
|
|
|
((level0_slowdown_writes_trigger - level0_file_num_compaction_trigger) / |
|
|
|
|
4); |
|
|
|
|
|
|
|
|
|
// overflow protection
|
|
|
|
|
if (one_fourth_trigger_slowdown < 0) { |
|
|
|
|
return std::numeric_limits<int>::max(); |
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
assert(twice_level0_trigger >= 0); |
|
|
|
|
assert(one_fourth_trigger_slowdown >= 0); |
|
|
|
|
|
|
|
|
|
// Or twice as compaction trigger, if it is smaller.
|
|
|
|
|
return std::min(twice_level0_trigger, one_fourth_trigger_slowdown); |
|
|
|
|
} |
|
|
|
|
} // namespace
|
|
|
|
|
|
|
|
|
|