Thanks Otis and Nikhil for your confirmation. I am more confident about the Lucene index integrity.
Nikhil, I don't see th reason why there is a corrupted .fdx file. Could it be caused by multi-threaded access to the index? Otis, I don't remember I asked about locking questions the other day. I think it should be another guy. Thanks all, Jian On 7/16/05, Otis Gospodnetic <[EMAIL PROTECTED]> wrote: > Hi Jian, > > Yes, I think what you describes is correct. You may end up with some > "junk index segments" in the index directory, but as long as they are > not recorded in segments file, they are irrelevant. > > Otis > P.S. > Did you ask you locking in Lucene the other day? > > > --- jian chen <[EMAIL PROTECTED]> wrote: > > > Hi, Otis, > > > > Thanks for your email. As this is very important for using Lucene in > > our production system, I looked at the code to try to understand. > > Here > > is my observation why the index won't be corrupted during a system > > crash. > > > > In the IndexWriter.java mergeSegments(...) method, there are two > > lines: > > segmentInfos.write(directory); // commit before deleting > > deleteSegments(segmentsToDelete);//delete unused segments > > > > The sgementInfos.write(...) writes the new segments file as > > "segments.new", once the write is complete, it renames "segments.new" > > to "segments". > > > > I guess the rename operation is atomic as guaranteed by the operating > > system. Otherwise, the "segments" file will be left in an > > inconsistent > > state during the system crash. > > > > It also appears to me that the "segments" file is the single point to > > switch from old set of index segments to new ones. In case of a > > system > > failure, the old "segments" file will be used anyway, so, no > > corruption. > > > > Is this understanding correct and thorough? > > > > Thanks a lot, > > > > Jian > > > > On 7/16/05, Otis Gospodnetic <[EMAIL PROTECTED]> wrote: > > > The only corruption that I've seen mentioned on this list so far > > was > > > the corruption of the segments file, and even that people have been > > > able to manually edit with a hex editor. > > > > > > Otis > > > > > > > > > --- jian chen <[EMAIL PROTECTED]> wrote: > > > > > > > Hi, > > > > > > > > I know Lucene does not have transaction support at this stage. > > > > However, I want to know what will happen if there is an operating > > > > system crash during the indexing process, will the Lucene index > > got > > > > corrupted? > > > > > > > > Thanks, > > > > > > > > Jian > > > > > > > > > > --------------------------------------------------------------------- > > > > 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] > > > > > > > > > > --------------------------------------------------------------------- > > 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]
