On Wed, Jun 27, 2018 at 10:44 PM Andres Freund <andres@xxxxxxxxxxx> wrote: > But I also can't reproduce it either on 10.4, 10-current, master. Did > you build from source? Packages? Any extensions? Is there anything > missing from the above instruction to reproduce this? Somehow today I cannot reproduce it by myself, I must have missed something since I cannot get locked out from the table. However I've tested that on 10.3 (one I've at the moment): 1) create table, insert, create index, reindex causes the problem but do not locks the further select 2) create table, create index, insert, reindex does not show the problem (i.e., no comlain at all) while on the following version both 1 and 2 shows the reading problem once the reindex is issued (but allows further selects): testdb=> select version(); version --------------------------------------------------------------------------------------------------------------------------------------------------------- PostgreSQL 11beta1 on x86_64-unknown-freebsd11.1, compiled by FreeBSD clang version 4.0.0 (tags/RELEASE_400/final 297347) (based on LLVM 4.0.0), 64-bit It seems not to depend on max_parallel_maintance_workers. Sorry, I cannot provide more help at the moment. I will try to reproduce it again. Luca