hi , Sorry to interrupt you, but I am really confused by the bad performance of lucene 4.2.1. Recently I migrated project from lucene 3.0 to 4.2.1 . After simply tests I found that both indexing and reading performance of lucene 4 can not match the older version.
Indexing code snippets are as follow: IndexWriterConfig iwc=new IndexWriterConfig(Version.LUCENE_42, new StandardAnalyzer(Version.LUCENE_42)); IndexWriter iw = new IndexWriter(NIOFSDirectory.open(file),iwc); for(){ document.add(filed); iw.addDocument(document); } iw.close(); Reading code snippets as follow: for(i=0;i<maxDoc;++i){ Document doc=indexsearcher.doc(i); for(j){ print(doc.get(column[j])); } } Plain text file is about 720MB , contains 6M records. Index File is 1.5GB in lucene3 and 1.1GB in lucene 4.2.1. When indexing , lucene 4 costs about two times time than lucene 3. and lucene 4 costs five times time than lucene3 when reading. After that I made another test, which is using lucene 4 reading index file indexed by lucene 3, and result is it is slower than lucene 3 reading index file indexed by lucene 3 , but faster than lucene 4 reading index file created by lucene 4 . Is that lucene 4 use more complex compression algorithm which makes smaller index file, but slow down the indexing and reading performance ? How to improve the this. Thanks for your time. Looking forward to your reply. Chris Zhang From Beijing,China