Thanks again Mike. In fact, I have just finished going throught the CHANGE.TXT file, that mentions the entire journey details of Lucene, right from 1.4 to 2.3. And of course, got to know many more things.
Just a couple of issues more. Firstly, in the 2.3 optimizations, point 4 says :: " 4. LUCENE-959: Remove synchronization in Document (yonik)". Well, what does that mean, since it has already been assured that multiple adds, deletes, updates CAN be done by multiple threads on a single IndexWriter instance. Secondly, this multiple-threads-doing-simultaneous-adds-deletes-modifies works for me in 2.3; moreover, the source code has also confirmed this ( in the IndexWriter.java file). However, does this hold true to prior 2.3 versions also ( I see that you state that multiple threads using same instances has "always" been fine, but just want to confirm it once again, as to exactly from when on .. ). Sorry, if I sound a little too demanding, but the fact is that I have just completed my multi-threader project using 2.3.0 jar after a lot of head-banging, and wish to know, that will everthing go well prior to 2.3.0, as far as multiple-threads-involved-in-multiple-simultaneous-adds/deletes/modofies-on-a-single-indexwriter-instance is concerned. Thanks Ajay Garg Michael McCandless-2 wrote: > > > The write.lock has always been to prevent multiple instances of > IndexWriter (or, IndexReader doing deletes) from operating on the > same index at a time. > > Many threads sharing a single instance of these classes has always > been fine. > > Mike > > ajay_garg wrote: > >> >> @Mike. >> >> Thanks for the reply. But I had thought that write.lock is there to >> prevent >> multiple additions/updates/deleteDocuments. >> >> Has there been a change recently in this regard ? >> >> Thanks >> Ajay Garg >> >> >> >> Michael McCandless-2 wrote: >>> >>> >>> That's right. >>> >>> Each thread can enter IndexWriter.add/update/deleteDocument(s) in >>> parallel. There are some parts inside IndexWriter that are >>> synchronized but they are kept to a minimum to keep good thread >>> concurrency. As you add threads it's best to increase the RAM buffer >>> at the same time to get better performance. >>> >>> Mike >>> >>> ajay_garg wrote: >>> >>>> >>>> @Yonik >>>> >>>> So you mean to say, that if two threads have the same instance of an >>>> IndexWriter passed to both of them, and both these threads run on >>>> two >>>> different CPUs, then they can write to the index at the same time ? >>>> >>>> >>>> >>>> Yonik Seeley wrote: >>>>> >>>>> On Jan 30, 2008 10:59 PM, ajay_garg >>>>> <[EMAIL PROTECTED]> wrote: >>>>>> >>>>>> Thanks Mike for your directions. >>>>>> >>>>>> Yes, I am in fact using a single computer for my application, and >>>>>> your >>>>>> saying that in this case, multiple threads with a single >>>>>> IndexWriter wll >>>>>> give a better performance. Hmmm. I just wonder that since each >>>>>> IndexWriter >>>>>> has a single write.lock, this means that sitting on the CPU, we >>>>>> observe >>>>>> that >>>>>> at a particular instant, only a single thread is using the CPU, >>>>> >>>>> The write.lock is to protect against other IndexWriter instances, >>>>> *not* against other threads. >>>>> Using multiple threads on a single IndexWriter should utilize >>>>> multiple >>>>> CPUs. >>>>> >>>>> -Yonik >>>>> >>>>> ------------------------------------------------------------------- >>>>> -- >>>>> To unsubscribe, e-mail: [EMAIL PROTECTED] >>>>> For additional commands, e-mail: [EMAIL PROTECTED] >>>>> >>>>> >>>>> >>>> >>>> -- >>>> View this message in context: http://www.nabble.com/Query-in- >>>> Lucene-2.3.0-tp15175141p15198783.html >>>> Sent from the Lucene - Java Users mailing list archive at >>>> Nabble.com. >>>> >>>> >>>> -------------------------------------------------------------------- >>>> - >>>> To unsubscribe, e-mail: [EMAIL PROTECTED] >>>> For additional commands, e-mail: [EMAIL PROTECTED] >>>> >>> >>> >>> --------------------------------------------------------------------- >>> To unsubscribe, e-mail: [EMAIL PROTECTED] >>> For additional commands, e-mail: [EMAIL PROTECTED] >>> >>> >>> >> >> -- >> View this message in context: http://www.nabble.com/Query-in- >> Lucene-2.3.0-tp15175141p15221338.html >> Sent from the Lucene - Java Users mailing list archive at Nabble.com. >> >> >> ------------------------------------------------------------ > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > > -- View this message in context: http://www.nabble.com/Query-in-Lucene-2.3.0-tp15175141p15255268.html Sent from the Lucene - Java Users mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
