根据
this或
this,我用多个线程使用相同的indexsearcher.但是当我从FsDirectory切换到MMapDirectory时,我有一些有趣的例外.
这个工作很好:
static void Main(string[] args) { DirectoryInfo directoryInfo = new DirectoryInfo(@"C:\Users\Tams\Desktop\new\"); var directory = FSDirectory.Open(directoryInfo); var indexSearcher = new IndexSearcher(directory); const int times = 100; const int concurrentTaskCount = 5; var task = new Task[concurrentTaskCount]; for (int i = 0; i < concurrentTaskCount; i++) { task[i] = new Task(() => Search(indexSearcher,times)); task[i].Start(); } Task.WaitAll(task); } static void Search(IndexSearcher reader,int times) { List<Document> docs = new List<Document>(10000); for (int i = 0; i < times; i++) { var q = new TermQuery(new Term("title","volume")); foreach (var scoreDoc in reader.Search(q,100).scoreDocs) { docs.Add(reader.Doc(scoreDoc.Doc)); } } }
但是用这个:
static void Main(string[] args) { DirectoryInfo directoryInfo = new DirectoryInfo(@"C:\Users\Tams\Desktop\new\"); var directory = new MMapDirectory(directoryInfo); // CHANGED var indexSearcher = new IndexSearcher(directory); const int times = 100; const int concurrentTaskCount = 5; var task = new Task[concurrentTaskCount]; for (int i = 0; i < concurrentTaskCount; i++) { task[i] = new Task(() => Search(indexSearcher,int times) { List<Document> docs = new List<Document>(10000); for (int i = 0; i < times; i++) { var q = new TermQuery(new Term("title",100).scoreDocs) { docs.Add(reader.Doc(scoreDoc.Doc)); } } }
我得到各种异常,如:
System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index at System.ThrowHelper.ThrowArgumentOutOfRangeException() at System.Collections.Generic.List`1.get_Item(Int32 index) at Lucene.Net.Index.FieldInfos.FieldInfo(Int32 fieldNumber) in d:\Lucene.Net\FullRepo\trunk\src\core\Index\FieldInfos.cs:line 378 at Lucene.Net.Index.FieldsReader.Doc(Int32 n,FieldSelector fieldSelector) in d:\Lucene.Net\FullRepo\trunk\src\core\Index\FieldsReader.cs:line 234 at Lucene.Net.Index.SegmentReader.Document(Int32 n,FieldSelector fieldSelector) in d:\Lucene.Net\FullRepo\trunk\src\core\Index\SegmentReader.cs:line 1193 at Lucene.Net.Index.DirectoryReader.Document(Int32 n,FieldSelector fieldSelector) in d:\Lucene.Net\FullRepo\trunk\src\core\Index\DirectoryReader.cs:line 686 at Lucene.Net.Index.IndexReader.Document(Int32 n) in d:\Lucene.Net\FullRepo\trunk\src\core\Index\IndexReader.cs:line 732 at Lucene.Net.Search.IndexSearcher.Doc(Int32 i) in d:\Lucene.Net\FullRepo\trunk\src\core\Search\IndexSearcher.cs:line 162 at PerformanceTest.Program.Search(IndexSearcher reader,Int32 times) in c:\Users\Tams\Documents\Visual Studio 2012\Projects\BookCatalog\PerformanceTest\Program.cs:line 28 at PerformanceTest.Program.<>c__DisplayClass2.<Main>b__0() in c:\Users\Tams\Documents\Visual Studio 2012\Projects\BookCatalog\PerformanceTest\Program.cs:line 43 at System.Threading.Tasks.Task.InnerInvoke() at System.Threading.Tasks.Task.Execute()
要么
System.IO.IOException: read past EOF at Lucene.Net.Store.BufferedIndexInput.Refill() in d:\Lucene.Net\FullRepo\trunk\src\core\Store\BufferedIndexInput.cs:line 179 at Lucene.Net.Store.BufferedIndexInput.ReadByte() in d:\Lucene.Net\FullRepo\trunk\src\core\Store\BufferedIndexInput.cs:line 41 at Lucene.Net.Store.IndexInput.ReadVInt() in d:\Lucene.Net\FullRepo\trunk\src\core\Store\IndexInput.cs:line 88 at Lucene.Net.Index.FieldsReader.Doc(Int32 n,FieldSelector fieldSelector) in d:\Lucene.Net\FullRepo\trunk\src\core\Index\FieldsReader.cs:line 230 at Lucene.Net.Index.SegmentReader.Document(Int32 n,FieldSelector fieldSelector) in d:\Lucene.Net\FullRepo\trunk\src\core\Index\DirectoryReader.cs:line 686 at Lucene.Net.Index.IndexReader.Document(Int32 n) in d:\Lucene.Net\FullRepo\trunk\src\core\Index\IndexReader.cs:line 732 at Lucene.Net.Search.IndexSearcher.Doc(Int32 i) in d:\Lucene.Net\FullRepo\trunk\src\core\Search\IndexSearcher.cs:line 162 at PerformanceTest.Program.Search(IndexSearcher reader,Int32 times) in c:\Users\Tams\Documents\Visual Studio 2012\Projects\BookCatalog\PerformanceTest\Program.cs:line 28 at PerformanceTest.Program.<>c__DisplayClass2.<Main>b__0() in c:\Users\Tams\Documents\Visual Studio 2012\Projects\BookCatalog\PerformanceTest\Program.cs:line 43 at System.Threading.Tasks.Task.InnerInvoke() at System.Threading.Tasks.Task.Execute()
最后一个代码工作正常,将concurrentTaskCount变量设置为1.
我错过了什么吗?我不明白是什么
其实我没有道路
d:\Lucene.Net\FullRepo\trunk\src\core\Store\BufferedIndexInput.cs
我甚至没有一个驱动器用字母“d”
解决方法
source for MMapDirectory显示,这个类没有按预期使用
memory-mapped files.它使用MemoryStream对象将所有索引文件加载到内存中,我猜这些流是不同线程寻找和读取时的问题的原因.
您可以通过将其加载到RAMDirectory中来获取基于内存的索引.这通过你的测试. (但是它是MMapDirectory目前所做的,不一定是你期望做的…)
var fsDirectory = FSDirectory.Open(directoryInfo); var directory = new RAMDirectory(fsDirectory);