postgres 10.3 no response

Hello!

In versions 10.1 and 10.3, an error was detected.

When performing parallel loading of data into a partitioned table (300 partitions), the PostgreSQL DBMS enters the "no response" state. No new connections are possible.

All processes are waiting for the release of the semaphore.

OS version
Linux asu-oko-test 3.0.101-77-ppc64 #1 SMP Tue Jun 14 20:33:58 UTC 2016 (a082ea6) ppc64 ppc64 ppc64 GNU/Linux

Postgresql version
PostgreSQL 10.3 on powerpc64-unknown-linux-gnu, compiled by gcc-5 (SUSE Linux) 5.3.1 20160301 [gcc-5-branch revision 233849], 64-bit

Test case in the attachment