On Tue, Feb 26, 2019 at 2:58 PM Amit Kapila <amit.kapil...@gmail.com> wrote: > > On Mon, Feb 25, 2019 at 10:32 PM Tom Lane <t...@sss.pgh.pa.us> wrote: > > > > To fix this symptom, we can ensure that once we didn't get any block > from local map, we must clear it. See the attached patch. I will try > to evaluate this code path to see if there is any similar race > condition and will also try to generate a reproducer. I don't have > any great idea to write a reproducer for this issue apart from trying > some thing similar to ecpg/test/thread/prep.pgc, if you can think of > any, I am all ears. >
I have tried this test many times (more than 1000 times) by varying thread count, but couldn't reproduce it. My colleague, Kuntal has tried a similar test overnight, but the issue didn't reproduce which is not surprising to me seeing the nature of the problem. As I could reproduce it via the debugger, I think we can go ahead with the fix. I have improved the comments in the attached patch and I have also tried to address Tom's concern w.r.t comments by adding additional comments atop of data-structure used to maintain the local map. Let me know what you think? -- With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com
fix_loc_map_clear_2.patch
Description: Binary data
