My assumption is that every query is relatively quick. If the times lapsed in other process when querying, the ensureIndexIsRead() function will not cause a lot of problems. If not, the ensureIndexIsRead() function will be a bottle neck. I could understand that a lot of systems' queries are quiet complex, so the problem may be gone. But for our system, more than 150 queries per seconds on a dual CPUs linux box, that's a problem.
If the queries became more complicated, we would ignore it in most of time. On 5/10/06, Doug Cutting <[EMAIL PROTECTED]> wrote:
The best search performance is achieved using a single IndexSearcher shared by multiple threads. Peter Keegan has demonstrated rates of up to 400 searches per second on eight-CPU machines using this approach: http://www.mail-archive.com/java-user@lucene.apache.org/msg05074.html So the synchronization is probably not hurting your performance. Doug yueyu lin wrote: > 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 > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
-- -- Yueyu Lin
