diff_leveldb.patch

diff --git a/db/dbformat.h b/db/dbformat.h
index 5d8a032..20cccec 100644
--- a/db/dbformat.h
+++ b/db/dbformat.h
@@ -25,10 +25,12 @@ static const int kNumLevels = 7;
 static const int kL0_CompactionTrigger = 4;
 
 // Soft limit on number of level-0 files.  We slow down writes at this point.
-static const int kL0_SlowdownWritesTrigger = 8;
+//static const int kL0_SlowdownWritesTrigger = 8;
+static const int kL0_SlowdownWritesTrigger = 4;
 
 // Maximum number of level-0 files.  We stop writes at this point.
-static const int kL0_StopWritesTrigger = 12;
+//static const int kL0_StopWritesTrigger = 12;
+static const int kL0_StopWritesTrigger = 4;
 
 // Maximum level to which a new compacted memtable is pushed if it
 // does not create overlap.  We try to push to level 2 to avoid the
diff --git a/db/version_set.cc b/db/version_set.cc
index aa83df5..f5d8937 100644
--- a/db/version_set.cc
+++ b/db/version_set.cc
@@ -1038,7 +1038,13 @@ void VersionSet::Finalize(Version* v) {
     } else {
       // Compute the ratio of current size to size limit.
       const uint64_t level_bytes = TotalFileSize(v->files_[level]);
-      score = static_cast<double>(level_bytes) / MaxBytesForLevel(level);
+      // score = static_cast<double>(level_bytes) / MaxBytesForLevel(level);
+	  // MSLS
+	  if (level < options_->custom_level_size_count)
+        score = static_cast<double>(level_bytes) / static_cast<double>(options_->custom_level_sizes[level]);
+	  else {
+        score = static_cast<double>(level_bytes) / MaxBytesForLevel(level);
+      }
     }
 
     if (score > best_score) {
@@ -1286,6 +1292,8 @@ Compaction* VersionSet::PickCompaction() {
     // c->inputs_[0] earlier and replace it with an overlapping set
     // which will include the picked file.
     current_->GetOverlappingInputs(0, &smallest, &largest, &c->inputs_[0]);
+    // MSLS - test
+    //current_->GetOverlappingInputs(0, NULL, NULL, &c->inputs_[0]);
     assert(!c->inputs_[0].empty());
   }
 
diff --git a/include/leveldb/options.h b/include/leveldb/options.h
index fdda718..a6955d4 100644
--- a/include/leveldb/options.h
+++ b/include/leveldb/options.h
@@ -135,6 +135,15 @@ struct Options {
   // Default: NULL
   const FilterPolicy* filter_policy;
 
+  // MSLS: Use custom level sizes if custom_level_size_count != 0.
+  // custom_level_size_count is the maximum level number to change the size.
+  // custom_level_sizes[i] specifies the maximum size of level-i (i < custom_level_size_count).
+  // custom_level_sizes[0] is ignored.
+  //
+  // Default: 0, NULL
+  size_t custom_level_size_count;
+  const size_t* custom_level_sizes;
+
   // Create an Options object with default values for all fields.
   Options();
 };
diff --git a/util/crc32c.cc b/util/crc32c.cc
index 6db9e77..7adb5f9 100644
--- a/util/crc32c.cc
+++ b/util/crc32c.cc
@@ -284,6 +284,9 @@ static inline uint32_t LE_LOAD32(const uint8_t *p) {
 }
 
 uint32_t Extend(uint32_t crc, const char* buf, size_t size) {
+  // MSLS
+  return 0;
+  /*
   const uint8_t *p = reinterpret_cast<const uint8_t *>(buf);
   const uint8_t *e = p + size;
   uint32_t l = crc ^ 0xffffffffu;
@@ -326,6 +329,7 @@ uint32_t Extend(uint32_t crc, const char* buf, size_t size) {
 #undef STEP4
 #undef STEP1
   return l ^ 0xffffffffu;
+  */
 }
 
 }  // namespace crc32c
diff --git a/util/options.cc b/util/options.cc
index 76af5b9..98ff188 100644
--- a/util/options.cc
+++ b/util/options.cc
@@ -22,7 +22,9 @@ Options::Options()
       block_size(4096),
       block_restart_interval(16),
       compression(kSnappyCompression),
-      filter_policy(NULL) {
+      filter_policy(NULL),
+      custom_level_size_count(0),
+      custom_level_sizes(NULL) {
 }