[
https://issues.apache.org/jira/browse/OMID-78?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16249535#comment-16249535
]
ASF GitHub Bot commented on OMID-78:
------------------------------------
Github user ebortnik commented on a diff in the pull request:
https://github.com/apache/incubator-omid/pull/16#discussion_r150531406
--- Diff:
hbase-coprocessor/src/main/java/org/apache/hadoop/hbase/regionserver/OmidRegionScanner.java
---
@@ -0,0 +1,128 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.hbase.regionserver;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.HRegionInfo;
+import org.apache.hadoop.hbase.regionserver.RegionScanner;
+import org.apache.hadoop.hbase.regionserver.ScannerContext;
+import org.apache.omid.transaction.HBaseTransaction;
+import org.apache.omid.transaction.SnapshotFilter;
+
+public class OmidRegionScanner implements RegionScanner {
+
+ RegionScanner scanner;
+ SnapshotFilter snapshotFilter;
+ HBaseTransaction transaction;
+ int maxVersions;
+ Map<String, List<Cell>> familyDeletionCache;
+
+ public OmidRegionScanner(SnapshotFilter snapshotFilter,
+ RegionScanner s,
+ HBaseTransaction transaction,
+ int maxVersions) {
+ this.snapshotFilter = snapshotFilter;
+ this.scanner = s;
+ this.transaction = transaction;
+ this.maxVersions = maxVersions;
+ this.familyDeletionCache = new HashMap<String, List<Cell>>();
+ }
+
+ @Override
+ public boolean next(List<Cell> results) throws IOException {
+ return next(results, Integer.MAX_VALUE);
+ }
+
+ public boolean next(List<Cell> result, int limit) throws IOException {
+ return nextRaw(result, limit);
+ }
+
+ @Override
+ public void close() throws IOException {
+ scanner.close();
+ }
+
+ @Override
+ public HRegionInfo getRegionInfo() {
+ return scanner.getRegionInfo();
+ }
+
+ @Override
+ public boolean isFilterDone() throws IOException {
+ return scanner.isFilterDone();
+ }
+
+ @Override
+ public boolean reseek(byte[] row) throws IOException {
+ throw new RuntimeException("Not implemented");
+ }
+
+ @Override
+ public long getMaxResultSize() {
+ return scanner.getMaxResultSize();
+ }
+
+ @Override
+ public long getMvccReadPoint() {
+ return scanner.getMvccReadPoint();
+ }
+
+ @Override
+ public boolean nextRaw(List<Cell> result) throws IOException {
--- End diff --
raw --> row
> Identify transaction snapshot at the server
> -------------------------------------------
>
> Key: OMID-78
> URL: https://issues.apache.org/jira/browse/OMID-78
> Project: Apache Omid
> Issue Type: New Feature
> Reporter: Ohad Shacham
> Assignee: Ohad Shacham
>
> To identify a transaction's snapshot in scans and gets, Omid reads and filter
> cells at the client side. This filtering requires checking the shadow cells
> and accessing the commit table if needed.
> Doing the filtering at the server side should be more efficient since less
> data is being transferred to the client and also, in some cases, RPCs are
> being saved.
> This feature requires implementing a coprocessor that will do the filtering
> at the server side and returns only the relevant snapshot to the client side.
> This feature is also needed to support the integration of Omid with Phoenix.
> This is required since Phoenix has coprocessors that change and condence the
> data returned to the client and therefore, filtering at the client side in
> this case is impossible.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
