[Opt](orc)Optimize the merge io when orc reader read multiple tiny stripes. (#42004) (#44239)

bp #42004

Co-authored-by: kaka11chen <kaka11.chen@gmail.com>

fe/fe-core/src/main/java/org/apache/doris/qe/SessionVariable.java

@@ -447,6 +447,12 @@ public class SessionVariable implements Serializable, Writable {
 
     public static final String ENABLE_ORC_LAZY_MAT = "enable_orc_lazy_materialization";
 
+    public static final String ORC_TINY_STRIPE_THRESHOLD_BYTES = "orc_tiny_stripe_threshold_bytes";
+
+    public static final String ORC_ONCE_MAX_READ_BYTES = "orc_once_max_read_bytes";
+
+    public static final String ORC_MAX_MERGE_DISTANCE_BYTES = "orc_max_merge_distance_bytes";
+
     public static final String ENABLE_PARQUET_FILTER_BY_MIN_MAX = "enable_parquet_filter_by_min_max";
 
     public static final String ENABLE_ORC_FILTER_BY_MIN_MAX = "enable_orc_filter_by_min_max";
@@ -1648,6 +1654,46 @@ public class SessionVariable implements Serializable, Writable {
     public boolean enableOrcLazyMat = true;
 
 
+    @VariableMgr.VarAttr(
+            name = ORC_TINY_STRIPE_THRESHOLD_BYTES,
+            description = {"在orc文件中如果一个stripe的字节大小小于`orc_tiny_stripe_threshold`,"
+                    + "我们认为该stripe为 tiny stripe。对于多个连续的tiny stripe我们会进行读取优化，即一次性读多个tiny stripe."
+                    + "如果你不想使用该优化，可以将该值设置为0。默认为 8M。",
+                    "In an orc file, if the byte size of a stripe is less than `orc_tiny_stripe_threshold`,"
+                            + "we consider the stripe to be a tiny stripe. For multiple consecutive tiny stripes,"
+                            + "we will perform read optimization, that is, read multiple tiny stripes at a time."
+                            + "If you do not want to use this optimization, you can set this value to 0."
+                            + "The default is 8M."},
+            needForward = true,
+            setter = "setOrcTinyStripeThresholdBytes")
+    public long orcTinyStripeThresholdBytes  = 8L * 1024L * 1024L;
+
+
+    @VariableMgr.VarAttr(
+            name = ORC_ONCE_MAX_READ_BYTES,
+            description = {"在使用tiny stripe读取优化的时候，会对多个tiny stripe合并成一次IO，"
+                    + "该参数用来控制每次IO请求的最大字节大小。你不应该将值设置的小于`orc_tiny_stripe_threshold`。默认为 8M。",
+                    "When using tiny stripe read optimization, multiple tiny stripes will be merged into one IO."
+                            + "This parameter is used to control the maximum byte size of each IO request."
+                            + "You should not set the value less than `orc_tiny_stripe_threshold`."
+                            + "The default is 8M."},
+            needForward = true,
+            setter = "setOrcOnceMaxReadBytes")
+    public long orcOnceMaxReadBytes = 8L * 1024L * 1024L;
+
+
+    @VariableMgr.VarAttr(
+            name = ORC_MAX_MERGE_DISTANCE_BYTES,
+            description = {"在使用tiny stripe读取优化的时候，由于tiny stripe并不一定连续。"
+                    + "当两个tiny stripe之间距离大于该参数时，我们不会将其合并成一次IO。默认为 1M。",
+                    "When using tiny stripe read optimization, since tiny stripes are not necessarily continuous,"
+                            + "when the distance between two tiny stripes is greater than this parameter,"
+                            + "we will not merge them into one IO. The default value is 1M."},
+            needForward = true,
+            setter = "setOrcMaxMergeDistanceBytes")
+    public long orcMaxMergeDistanceBytes = 1024L * 1024L;
+
+
     @VariableMgr.VarAttr(
             name = ENABLE_PARQUET_FILTER_BY_MIN_MAX,
             description = {"控制 parquet reader 是否启用 min-max 值过滤。默认为 true。",
@@ -2662,6 +2708,32 @@ public class SessionVariable implements Serializable, Writable {
         this.parallelExecInstanceNum = val;
     }
 
+    public void setOrcTinyStripeThresholdBytes(String value) throws Exception {
+        long val = checkFieldLongValue(ORC_TINY_STRIPE_THRESHOLD_BYTES, 0, value);
+        this.orcTinyStripeThresholdBytes = val;
+    }
+
+    public void setOrcOnceMaxReadBytes(String value)  throws Exception {
+        long val = checkFieldLongValue(ORC_ONCE_MAX_READ_BYTES, 0, value);
+        this.orcOnceMaxReadBytes = val;
+    }
+
+    public void setOrcMaxMergeDistanceBytes(String value)  throws Exception {
+        long val = checkFieldLongValue(ORC_MAX_MERGE_DISTANCE_BYTES, 0, value);
+        this.orcMaxMergeDistanceBytes = val;
+    }
+
+    private long checkFieldLongValue(String variableName, long minValue, String value) throws Exception {
+        long val = Long.parseLong(value);
+        if (val < minValue) {
+            throw new Exception(
+                    variableName + " value should greater than or equal " + String.valueOf(minValue)
+                            + ", you set value is: " + value);
+        }
+        return val;
+    }
+
+
     private int checkFieldValue(String variableName, int minValue, String value) throws Exception {
         int val = Integer.valueOf(value);
         if (val < minValue) {
@@ -3684,6 +3756,11 @@ public class SessionVariable implements Serializable, Writable {
         tResult.setAdaptivePipelineTaskSerialReadOnLimit(adaptivePipelineTaskSerialReadOnLimit);
         tResult.setInListValueCountThreshold(inListValueCountThreshold);
         tResult.setEnableAutoCreateWhenOverwrite(enableAutoCreateWhenOverwrite);
+
+        tResult.setOrcTinyStripeThresholdBytes(orcTinyStripeThresholdBytes);
+        tResult.setOrcMaxMergeDistanceBytes(orcMaxMergeDistanceBytes);
+        tResult.setOrcOnceMaxReadBytes(orcOnceMaxReadBytes);
+
         return tResult;
     }