[iotdb] branch research/M4-visualization updated: uncompress save time

[leirui]

This is an automated email from the ASF dual-hosted git repository.

leirui pushed a commit to branch research/M4-visualization
in repository https://gitbox.apache.org/repos/asf/iotdb.git


The following commit(s) were added to refs/heads/research/M4-visualization by 
this push:
     new 565f94701d uncompress save time
565f94701d is described below

commit 565f94701db091876e65c08269dfa309fb74bd97
Author: Lei Rui <1010953...@qq.com>
AuthorDate: Thu Apr 13 16:58:32 2023 +0800

    uncompress save time
---
 .../iotdb/tsfile/common/conf/TSFileConfig.java     |  2 +-
 .../tsfile/read/reader/chunk/ChunkReader.java      | 63 ++++++++++++----------
 2 files changed, 37 insertions(+), 28 deletions(-)

diff --git 
a/tsfile/src/main/java/org/apache/iotdb/tsfile/common/conf/TSFileConfig.java 
b/tsfile/src/main/java/org/apache/iotdb/tsfile/common/conf/TSFileConfig.java
index 2186a92162..b7ba5a57d5 100644
--- a/tsfile/src/main/java/org/apache/iotdb/tsfile/common/conf/TSFileConfig.java
+++ b/tsfile/src/main/java/org/apache/iotdb/tsfile/common/conf/TSFileConfig.java
@@ -111,7 +111,7 @@ public class TSFileConfig implements Serializable {
   /** Default DFT satisfy rate is 0.1 */
   private double dftSatisfyRate = 0.1;
   /** Data compression method, TsFile supports UNCOMPRESSED, SNAPPY or LZ4. */
-  private CompressionType compressor = CompressionType.SNAPPY;
+  private CompressionType compressor = CompressionType.UNCOMPRESSED;
   /** Line count threshold for checking page memory occupied size. */
   private int pageCheckSizeThreshold = 100;
   /** Default endian value is BIG_ENDIAN. */
diff --git 
a/tsfile/src/main/java/org/apache/iotdb/tsfile/read/reader/chunk/ChunkReader.java
 
b/tsfile/src/main/java/org/apache/iotdb/tsfile/read/reader/chunk/ChunkReader.java
index 2a4e1f7e4c..c794f87f78 100644
--- 
a/tsfile/src/main/java/org/apache/iotdb/tsfile/read/reader/chunk/ChunkReader.java
+++ 
b/tsfile/src/main/java/org/apache/iotdb/tsfile/read/reader/chunk/ChunkReader.java
@@ -25,6 +25,7 @@ import org.apache.iotdb.tsfile.encoding.decoder.Decoder;
 import org.apache.iotdb.tsfile.file.MetaMarker;
 import org.apache.iotdb.tsfile.file.header.ChunkHeader;
 import org.apache.iotdb.tsfile.file.header.PageHeader;
+import org.apache.iotdb.tsfile.file.metadata.enums.CompressionType;
 import org.apache.iotdb.tsfile.file.metadata.enums.TSDataType;
 import org.apache.iotdb.tsfile.file.metadata.enums.TSEncoding;
 import org.apache.iotdb.tsfile.file.metadata.statistics.Statistics;
@@ -137,37 +138,45 @@ public class ChunkReader implements IChunkReader {
   }
 
   private PageReader constructPageReaderForNextPage(PageHeader pageHeader) 
throws IOException {
-    int compressedPageBodyLength = pageHeader.getCompressedSize();
-    byte[] compressedPageBody = new byte[compressedPageBodyLength];
+    ByteBuffer pageData;
+    if (chunkHeader.getCompressionType() != CompressionType.UNCOMPRESSED) {
+      int compressedPageBodyLength = pageHeader.getCompressedSize();
+      byte[] compressedPageBody = new byte[compressedPageBodyLength];
+
+      // doesn't has a complete page body
+      if (compressedPageBodyLength > chunkDataBuffer.remaining()) {
+        throw new IOException(
+            "do not has a complete page body. Expected:"
+                + compressedPageBodyLength
+                + ". Actual:"
+                + chunkDataBuffer.remaining());
+      }
 
-    // doesn't has a complete page body
-    if (compressedPageBodyLength > chunkDataBuffer.remaining()) {
-      throw new IOException(
-          "do not has a complete page body. Expected:"
-              + compressedPageBodyLength
-              + ". Actual:"
-              + chunkDataBuffer.remaining());
-    }
+      chunkDataBuffer.get(compressedPageBody);
+      byte[] uncompressedPageData = new byte[pageHeader.getUncompressedSize()];
+      try {
+        unCompressor.uncompress(
+            compressedPageBody, 0, compressedPageBodyLength, 
uncompressedPageData, 0);
+      } catch (Exception e) {
+        throw new IOException(
+            "Uncompress error! uncompress size: "
+                + pageHeader.getUncompressedSize()
+                + "compressed size: "
+                + pageHeader.getCompressedSize()
+                + "page header: "
+                + pageHeader
+                + e.getMessage());
+      }
 
-    chunkDataBuffer.get(compressedPageBody);
+      pageData = ByteBuffer.wrap(uncompressedPageData);
+    } else {
+      // get a slice from chunkDataBuffer, and position chunkDataBuffer
+      pageData = chunkDataBuffer.slice();
+      pageData.limit(pageHeader.getCompressedSize());
+      chunkDataBuffer.position(chunkDataBuffer.position() + 
pageHeader.getCompressedSize());
+    }
     Decoder valueDecoder =
         Decoder.getDecoderByType(chunkHeader.getEncodingType(), 
chunkHeader.getDataType());
-    byte[] uncompressedPageData = new byte[pageHeader.getUncompressedSize()];
-    try {
-      unCompressor.uncompress(
-          compressedPageBody, 0, compressedPageBodyLength, 
uncompressedPageData, 0);
-    } catch (Exception e) {
-      throw new IOException(
-          "Uncompress error! uncompress size: "
-              + pageHeader.getUncompressedSize()
-              + "compressed size: "
-              + pageHeader.getCompressedSize()
-              + "page header: "
-              + pageHeader
-              + e.getMessage());
-    }
-
-    ByteBuffer pageData = ByteBuffer.wrap(uncompressedPageData);
     PageReader reader =
         new PageReader(
             pageHeader, pageData, chunkHeader.getDataType(), valueDecoder, 
timeDecoder, filter);