tsdbCache/skyline: first round skyline detection

source/dnode/vnode/src/tsdb/tsdbCache.c

@@ -18,7 +18,8 @@
 int32_t tsdbOpenCache(STsdb *pTsdb) {
   int32_t    code = 0;
   SLRUCache *pCache = NULL;
-  size_t     cfgCapacity = 1024 * 1024;  // TODO: get cfg from tsdb config
+  // TODO: get cfg from vnode config: pTsdb->pVnode->config.lruCapacity
+  size_t cfgCapacity = 1024 * 1024;
 
   pCache = taosLRUCacheInit(cfgCapacity, -1, .5);
   if (pCache == NULL) {
@@ -61,8 +62,11 @@ int32_t tsdbCacheInsertLastrow(SLRUCache *pCache, tb_uid_t uid, STSRow *row) {
   if (h) {
     cacheRow = (STSRow *)taosLRUCacheValue(pCache, h);
     if (row->ts >= cacheRow->ts) {
-      if (row->ts > cacheRow->ts) {
+      if (TD_ROW_LEN(row) <= TD_ROW_LEN(cacheRow)) {
         tdRowCpy(cacheRow, row);
+      } else {
+        tsdbCacheDeleteLastrow(pCache, uid);
+        tsdbCacheInsertLastrow(pCache, uid, row);
       }
     }
   } else {
@@ -475,13 +479,39 @@ static STSRow *tsRowFromTsdbRow(TSDBROW *pRow) {
   // TODO: new tsrow from tsdbrow
   STSRow *ret = NULL;
   if (pRow->type == 0) {
-    return pRow->pTSRow;
+    return tdRowDup(pRow->pTSRow);
   } else {
   }
 
   return ret;
 }
 
+static bool tsdbKeyDeleted(TSDBKEY *key, SArray *pSkyline, int *iSkyline) {
+  bool deleted = false;
+  while (*iSkyline > 0) {
+    TSDBKEY *pItemBack = (TSDBKEY *)taosArrayGet(pSkyline, *iSkyline);
+    TSDBKEY *pItemFront = (TSDBKEY *)taosArrayGet(pSkyline, *iSkyline - 1);
+
+    if (key->ts > pItemBack->ts) {
+      return false;
+    } else if (key->ts >= pItemFront->ts && key->ts <= pItemBack->ts) {
+      if ((key->version <= pItemFront->version || key->ts == pItemBack->ts && key->version <= pItemBack->version)) {
+        return true;
+      } else {
+        return false;
+      }
+    } else {
+      if (*iSkyline > 1) {
+        --*iSkyline;
+      } else {
+        return false;
+      }
+    }
+  }
+
+  return deleted;
+}
+
 typedef int32_t (*_next_row_fn_t)(void *iter, TSDBROW **ppRow);
 
 typedef struct TsdbNextRowState {
@@ -598,8 +628,8 @@ static int32_t mergeLastRow(tb_uid_t uid, STsdb *pTsdb, STSRow **ppRow) {
     for (int i = 0; i < nMax; ++i) {
       TSDBKEY maxKey = TSDBROW_KEY(max[i]);
 
-      bool deleted = false;
-      // bool deleted = tsdbKeyDeleted(maxKey, pSkyline, &iSkyline);
+      // bool deleted = false;
+      bool deleted = tsdbKeyDeleted(&maxKey, pSkyline, &iSkyline);
       if (!deleted) {
         merge[nMerge++] = max[i];
       }