Thanks Erick for quick response, really appreciate it. Sorry, for some reason, I did not get the response in email and just searched the web and
found your response, :) Huaxiang 1> No. There's really no "index queue". Current batches being processed are finished, then the commit happens. HX: Got it. 2,3> The key is the "segments" file in your index, there should only be one of those. At time T, the segments file "points" to, say, segments 1, 2, 3. Now segments 4, 5 and 6 are written (but no commit). If you killed Solr with, say, a kill -9 or Solr crashed, you'd only see segments 1, 2, 3. Contrast that with a commit. The last act after closing all current segments is to rewrite the segments_n file to include segments 1, 2, 3, 4, 5, 6. Or say you had segments 1, 2, 3 as above and segments 2 and 3 were merged into segment 4. After the merge was completed, the segments file would point to segments 1 and 4, and after it was safely written segments 2 and 3 would be deleted. HX: So the magic is segments file, well explained, thanks. final question: How is it "not working"? Once you execute the "ant idea" command successfully, you should just be able to open the project from IntelliJ. Occasionally I have to run an "ant clean-idea idea" to start over, but I do this very often. In general, when i debug Solr I don't try to run Solr from within intellij. I build it externally (execute 'ant server' in the Solr directory then start it up). Then I debug Solr remotely. If I'm trying to debug something specific, it's often easiest to do from a unit test. I don't try to build the entire project from within IntelliJ although I think others do. Mostly I just don't want to have one extra variable in the equation... HX: Thanks for sharing. I tried to load lucene-solr in intellij and do source code reading s so I can use intellij to find out all usage of methods and all implementations of one class. Due to unresolved variables/methods, this is hard. Let me try it again. On Thu, Feb 7, 2019 at 12:34 PM Huaxiang Sun <huaxiang...@gmail.com> wrote: Hi Devs, I am a newbie to solr/lucene project and have some questions about index hard commit. Excuse me if these have been asked before. 1. When hard commit happens, will it drain up entries in the index queue? 2. How exactly is index file written? I.e, will they be written to tmp dir and moved to the index dir when it completes, or they are written to the index dir directly. In the later case, if one is reading the index dir, then it can read incomplete index files. 3. Similar question to index merge. Will the merge process create merged file in tmp dir and moved to index dir after merge completes? When are these files merged deleted? Will these merged files be moved to some archive dir and cleaned up later or deleted right after the merge? The final question is about intellij setup for lucene/solr project. I followed the steps in doc and it seems that the code browsing/build does not work well for me. Just want to check that these are steps I need to follow. Thanks Huaxiang Sun
