One IndexSearcher is one IndexSearcher instance. The instance has a lot of functions. Unfortunately they will call another synchronized function in other class's instance (TermInfosReader). That's the point why we need two IndexSearchers. But two searchers will cost double cache memory. It's not worthy. So if Lucene team can modify the codes slightly, the synchronization problem will be gone.
On 5/9/06, Chris Hostetter <[EMAIL PROTECTED]> wrote:
: We found if we were using 2 IndexSearcher, we would get 10% performance : benefit. : But if we increased the number of IndexSearcher from 2, the performance : improvement became slight even worse. Why use more then 2 IndexSearchers? Typically 1 is all you need, except for when you want to open and "warm up" a new Searcher because you know your index has changed on disk and you're ready for those changes to be visible. (I'm not arguing against your change -- concurrancy isn't my forte so i have no opinion on wether your suggesting is good or not, i'm just questioning the goal) Acctually .. i don't know a lot about the internals of IndexSearcher and TermInfosReader, but according to your description of the problem... : The class org.apache.lucene.index.TermInfosReader , as you know, every : IndexSearcher will have one TermInfosReader. Every query, one method in the : class must be called: : private synchronized void ensureIndexIsRead() throws IOException . Notice If the method isn't static, then how can two differnet instances of IndexSearcher, each with their own TermInfosReader, block one another? -Hoss --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
-- -- Yueyu Lin
