add index for tags-to-documents

Now we can find writer much faster, because we don't have to execute
a query for documents that match the tags. We can just look up the 
documents in the map.
Speedup: 2-4ms -> 0.002-0.01ms

data-store/src/main/java/org/lucares/pdb/datastore/PdbDB.java

@@ -39,4 +39,8 @@ public class PdbDB {
 		return proposer.propose(query, caretIndex);
 	}
 
+	public List<Doc> getByTags(Tags tags) {
+		
+		return dataStore.getByTags(tags);
+	}
 }

data-store/src/main/java/org/lucares/pdb/datastore/internal/DataStore.java

@@ -49,7 +49,9 @@ public class DataStore {
 	// to be guarded by itself
 	private final List<Doc> docIdToDoc = new ArrayList<>();
 	
-	private final Map<String, Map<String, IntList>> keyToValueToDocId = new ConcurrentHashMap<>();
+	private final ConcurrentHashMap<Tags, List<Doc>> tagsToDocs = new ConcurrentHashMap<>();
+
+	private final ConcurrentHashMap<String, Map<String, IntList>> keyToValueToDocId = new ConcurrentHashMap<>();
 
 	private final StringCompressor stringCompressor;
 	private final FolderStorage folderStorage;
@@ -81,11 +83,18 @@ public class DataStore {
 	private void cacheTagToFileMapping(final Tags tags, final Path path) {
 
 		final int docId;
+		final Doc newDoc = new Doc(tags, path);
 		synchronized (docIdToDoc) {			
 			docId = docIdToDoc.size();
-			docIdToDoc.add(new Doc(tags, path));
+			docIdToDoc.add(newDoc);
 		}
 		
+		tagsToDocs.compute(tags, (t, listOfDocs) -> {
+			final List<Doc> result = listOfDocs != null ? listOfDocs : new ArrayList<>(2);
+			result.add(newDoc);
+			return result;
+		});
+		
 		for (final String key : tags.getKeys()) {
 			final Map<String, IntList> valueToDocIds = keyToValueToDocId.computeIfAbsent(key, k -> new ConcurrentHashMap<>());
 
@@ -280,4 +289,9 @@ public class DataStore {
 		}
 		return result;
 	}
+
+	public List<Doc> getByTags(Tags tags) {
+		final List<Doc> result = tagsToDocs.getOrDefault(tags, new ArrayList<>(0));
+		return result;
+	}
 }

data-store/src/test/java/org/lucares/pdb/datastore/internal/DataStoreTest.java

@@ -12,7 +12,6 @@ import java.util.Map.Entry;
 
 import org.lucares.pdb.api.Tags;
 import org.lucares.pdb.datastore.Doc;
-import org.lucares.pdb.datastore.internal.DataStore;
 import org.lucares.utils.CollectionUtils;
 import org.lucares.utils.file.FileUtils;
 import org.testng.Assert;
@@ -99,6 +98,28 @@ public class DataStoreTest {
 
 	}
 	
+	public void testGetByTags() throws IOException
+	{
+		final Tags eagleTim1 = Tags.create("bird", "eagle", "name", "Tim");
+		final Tags eagleTim2 = Tags.create("bird", "eagle", "name", "Tim");
+		final Tags pigeonJennifer = Tags.create("bird", "pigeon", "name", "Jennifer");
+		final Tags flamingoJennifer = Tags.create("bird", "flamingo", "name", "Jennifer");
+		
+		dataStore = new DataStore(dataDirectory);
+		
+		dataStore.createNewFile(eagleTim1);
+		dataStore.createNewFile(eagleTim2);
+		dataStore.createNewFile(pigeonJennifer);
+		dataStore.createNewFile(flamingoJennifer);
+		
+		// eagleTim1 and eagleTim2 have the same tags, so we find both docs
+		final List<Doc> docsEagleTim = dataStore.getByTags(eagleTim1);
+		Assert.assertEquals(docsEagleTim.size(), 2, "two docs for eagleTim1 and eagleTim2");
+		
+		final List<Doc> docsFlamingoJennifer = dataStore.getByTags(flamingoJennifer);
+		Assert.assertEquals(docsFlamingoJennifer.size(), 1, "doc for docsFlamingoJennifer");
+	}
+
 	private void assertSearch(final String query, final Tags... tags) {
 		final List<Doc> actualDocs = dataStore.search(query);
 		final List<Path> actual = CollectionUtils.map(actualDocs, Doc::getPath);

pdb-ui/src/main/resources/log4j2.xml

@@ -38,6 +38,7 @@
   	<logger name="org.lucares.metrics.proposals" level="DEBUG" />
   	<logger name="org.lucares.metrics.plotter" level="DEBUG" />
   	<logger name="org.lucares.metrics.gnuplot" level="DEBUG" />
+  	<logger name="org.lucares.metrics.ingestion.tagsToFile.newPdbWriter" level="DEBUG" />
   	<!-- 
   	<logger name="org.lucares.metrics.dataStore" level="DEBUG" />
   	<logger name="org.lucares.pdb.datastore.lang.QueryCompletionPdbLangParser" level="TRACE" />

performanceDb/src/main/java/org/lucares/performance/db/TagsToFile.java

@@ -12,9 +12,7 @@ import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Objects;
 import java.util.Optional;
-import java.util.Set;
 import java.util.function.Consumer;
-import java.util.stream.Collectors;
 
 import org.lucares.pdb.api.Tags;
 import org.lucares.pdb.datastore.Doc;
@@ -26,7 +24,8 @@ import org.slf4j.LoggerFactory;
 public class TagsToFile implements AutoCloseable {
 
 	private static final Logger LOGGER = LoggerFactory.getLogger(TagsToFile.class);
-	private final static Logger METRICS_LOGGER = LoggerFactory.getLogger("org.lucares.metrics.ingestion.tagsToFile");
+	private final static Logger METRICS_LOGGER_FIND_WRITER = LoggerFactory.getLogger("org.lucares.metrics.ingestion.tagsToFile.findWriter");
+	private final static Logger METRICS_LOGGER_NEW_WRITER = LoggerFactory.getLogger("org.lucares.metrics.ingestion.tagsToFile.newPdbWriter");
 
 	private static class WriterCache {
 		final List<PdbWriter> writers = new ArrayList<>();
@@ -53,25 +52,23 @@ public class TagsToFile implements AutoCloseable {
 	}
 
 	private List<PdbFile> getFilesMatchingTagsExactly(final Tags tags) {
-		final List<PdbFile> files = getFilesMatchingTags(tags);
+		final List<Doc> docs = db.getByTags(tags);
-
+		return toPdbFiles(docs);
-		return CollectionUtils.filter(files, f -> f.getTags().equals(tags));
-	}
-
-	private List<PdbFile> getFilesMatchingTags(final Tags tags) {
-		final String query = Query.createQuery(tags);
-
-		return getFilesForQuery(query);
 	}
 
 	public List<PdbFile> getFilesForQuery(final String query) {
-		final List<PdbFile> result = new ArrayList<>();
 		
 		final List<Doc> searchResult = db.search(query);
 		if (searchResult.size() > 500_000){
 			throw new IllegalStateException("Too many results.");
 		}
 
+		final List<PdbFile> result = toPdbFiles(searchResult);
+		return result;
+	}
+
+	private List<PdbFile> toPdbFiles(final List<Doc> searchResult) {
+		final List<PdbFile> result = new ArrayList<>();
 		for (final Doc document : searchResult) {
 
 			final Path path = document.getPath();
@@ -80,7 +77,6 @@ public class TagsToFile implements AutoCloseable {
 
 			result.add(pdbFile);
 		}
-
 		return result;
 	}
 
@@ -97,15 +93,13 @@ public class TagsToFile implements AutoCloseable {
 			final long start = System.nanoTime();
 			final List<PdbFile> pdbFiles = getFilesMatchingTagsExactly(tags);
 
-			assertAllFilesHaveSameFolder(pdbFiles);
-
 			pdbFiles.removeIf(f -> !f.exists());
 			final List<Optional<PdbWriter>> optionalWriters = CollectionUtils.map(pdbFiles, writersForTags::writer);
 			final List<Optional<PdbWriter>> existingWriters = CollectionUtils.filter(optionalWriters,
 					Optional::isPresent);
 			final List<PdbWriter> writers = CollectionUtils.map(existingWriters, Optional::get);
 			
-			METRICS_LOGGER.debug("find writers took {}ms for tags {}", (System.nanoTime() - start)
+			METRICS_LOGGER_FIND_WRITER.debug("find writers took {}ms for tags {}", (System.nanoTime() - start)
 					/ 1_000_000.0, tags);
 
 			final Optional<PdbWriter> optionalFirst = chooseBestMatchingWriter(writers, date);
@@ -163,27 +157,20 @@ public class TagsToFile implements AutoCloseable {
 	}
 
 	private PdbWriter newPdbWriter(final Tags tags) {
+		final long start = System.nanoTime();
 		try {
 			final PdbFile pdbFile = createNewPdbFile(tags);
 			final PdbWriter result = new PdbWriter(pdbFile);
 
 			getOrInit(tags).addWriter(result);
+			
+			METRICS_LOGGER_NEW_WRITER.debug("newPdbWriter took {}ms tags: ", (System.nanoTime() - start) / 1_000_000.0, tags);
+			
 			return result;
 		} catch (final IOException e) {
 			throw new WriteException(e);
 		}
-	}
 		
-	private void assertAllFilesHaveSameFolder(final List<PdbFile> pdbFiles) {
-		final Set<Path> reducedFolder = pdbFiles.stream()//
-				.map(PdbFile::getPath)//
-				.map(p -> p.getParent().getParent().getParent())//
-				.collect(Collectors.toSet());
-
-		if (reducedFolder.size() > 1) {
-			throw new IllegalStateException(
-					"All storage folders for the same tag must be the same, but are not: " + reducedFolder);
-		}
 	}
 
 	private PdbFile createNewPdbFile(final Tags tags) throws IOException {