Unlogged tables cleanup

Hi, hackers

I wonder if such behavior can be considered as a bug:

knizhnik@knizhnik:~/dtm-data$ psql postgres
psql (10devel)
Type "help" for help.

postgres=# create tablespace fs location '/home/knizhnik/dtm-data/fs';
CREATE TABLESPACE
postgres=# set default_tablespace=fs;
SET
postgres=# create unlogged table foo(x integer);
CREATE TABLE
postgres=# insert into foo values(generate_series(1,100000));
INSERT 0 100000



Now simulate server crash using using "pkill -9 postgres".

knizhnik@knizhnik:~/dtm-data$ rm -f logfile ; pg_ctl -D pgsql.master -l 
logfile start
pg_ctl: another server might be running; trying to start server anyway
server starting
knizhnik@knizhnik:~/dtm-data$ psql postgres
psql (10devel)
Type "help" for help.

postgres=# select * from foo;
ERROR:  could not open file 
"pg_tblspc/16384/PG_10_201611041/12289/16385": No such file or directory

knizhnik@knizhnik:~/dtm-data$ ls fs
PG_10_201611041
knizhnik@knizhnik:~/dtm-data$ ls fs/PG_10_201611041/


So all relation directory is removed!
It happens only for first table created in tablespace.
If you create table in Postgres data directory everything is ok: first 
segment of relation is truncated but not deleted.
Also if you create one more unlogged table in tablespace it is truncated 
correctly:

postgres=# set default_tablespace=fs;
SET
postgres=# create unlogged table foo1(x integer);
CREATE TABLE
postgres=# insert into foo1 values(generate_series(1,100000));
INSERT 0 100000
postgres=# \q
knizhnik@knizhnik:~/dtm-data$ pkill -9 postgres
knizhnik@knizhnik:~/dtm-data$ rm -f logfile ; pg_ctl -D pgsql.master -l 
logfile start
pg_ctl: another server might be running; trying to start server anyway
server starting
knizhnik@knizhnik:~/dtm-data$ psql postgres
psql (10devel)
Type "help" for help.

postgres=# select * from foo1; x
---
(0 rows)

knizhnik@knizhnik:~/dtm-data$ ls -l fs/PG_10_201611041/12289/*
-rw------- 1 knizhnik knizhnik 0 Nov  9 19:52 fs/PG_10_201611041/12289/32768
-rw------- 1 knizhnik knizhnik 0 Nov  9 19:52 
fs/PG_10_201611041/12289/32768_init


-- 
Konstantin Knizhnik
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company