Re: [HACKERS] Parallel Append implementation

On Thu, Nov 23, 2017 at 2:22 PM, amul sul <sulamul(at)gmail(dot)com> wrote:
> Look like it is the same crash what v20 claim to be fixed, indeed I
> missed to add fix[1] in v20 patch, sorry about that. Attached updated
> patch includes aforementioned fix.

Hi,

I have applied latest v21 patch, it got crashed when enabled
partition-wise-join,
same query is working fine with and without partition-wise-join
enabled on PG-head.
please take a look.

SET enable_partition_wise_join TO true;

CREATE TABLE pt1 (a int, b int, c text, d int) PARTITION BY LIST(c);
CREATE TABLE pt1_p1 PARTITION OF pt1 FOR VALUES IN ('0000', '0001',
'0002', '0003');
CREATE TABLE pt1_p2 PARTITION OF pt1 FOR VALUES IN ('0004', '0005',
'0006', '0007');
CREATE TABLE pt1_p3 PARTITION OF pt1 FOR VALUES IN ('0008', '0009',
'0010', '0011');
INSERT INTO pt1 SELECT i % 20, i % 30, to_char(i % 12, 'FM0000'), i %
30 FROM generate_series(0, 99999) i;
ANALYZE pt1;

CREATE TABLE pt2 (a int, b int, c text, d int) PARTITION BY LIST(c);
CREATE TABLE pt2_p1 PARTITION OF pt2 FOR VALUES IN ('0000', '0001',
'0002', '0003');
CREATE TABLE pt2_p2 PARTITION OF pt2 FOR VALUES IN ('0004', '0005',
'0006', '0007');
CREATE TABLE pt2_p3 PARTITION OF pt2 FOR VALUES IN ('0008', '0009',
'0010', '0011');
INSERT INTO pt2 SELECT i % 20, i % 30, to_char(i % 12, 'FM0000'), i %
30 FROM generate_series(0, 99999) i;
ANALYZE pt2;

EXPLAIN ANALYZE
SELECT t1.c, sum(t2.a), COUNT(*) FROM pt1 t1 FULL JOIN pt2 t2 ON t1.c
= t2.c GROUP BY t1.c ORDER BY 1, 2, 3;
WARNING: terminating connection because of crash of another server process
DETAIL: The postmaster has commanded this server process to roll back
the current transaction and exit, because another server process
exited abnormally and possibly corrupted shared memory.
HINT: In a moment you should be able to reconnect to the database and
repeat your command.
server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.
!>

stack-trace is given below.

Core was generated by `postgres: parallel worker for PID 73935
'.
Program terminated with signal 11, Segmentation fault.
#0 0x00000000006dc4b3 in ExecProcNode (node=0x7f7f7f7f7f7f7f7e) at
../../../src/include/executor/executor.h:238
238 if (node->chgParam != NULL) /* something changed? */
Missing separate debuginfos, use: debuginfo-install
keyutils-libs-1.4-5.el6.x86_64 krb5-libs-1.10.3-65.el6.x86_64
libcom_err-1.41.12-23.el6.x86_64 libselinux-2.0.94-7.el6.x86_64
openssl-1.0.1e-57.el6.x86_64 zlib-1.2.3-29.el6.x86_64
(gdb) bt
#0 0x00000000006dc4b3 in ExecProcNode (node=0x7f7f7f7f7f7f7f7e) at
../../../src/include/executor/executor.h:238
#1 0x00000000006dc72e in ExecAppend (pstate=0x26cd6e0) at nodeAppend.c:207
#2 0x00000000006d1e7c in ExecProcNodeInstr (node=0x26cd6e0) at
execProcnode.c:446
#3 0x00000000006dcee5 in ExecProcNode (node=0x26cd6e0) at
../../../src/include/executor/executor.h:241
#4 0x00000000006dd38c in fetch_input_tuple (aggstate=0x26cd7f8) at
nodeAgg.c:699
#5 0x00000000006e02eb in agg_fill_hash_table (aggstate=0x26cd7f8) at
nodeAgg.c:2536
#6 0x00000000006dfb2b in ExecAgg (pstate=0x26cd7f8) at nodeAgg.c:2148
#7 0x00000000006d1e7c in ExecProcNodeInstr (node=0x26cd7f8) at
execProcnode.c:446
#8 0x00000000006d1e4d in ExecProcNodeFirst (node=0x26cd7f8) at
execProcnode.c:430
#9 0x00000000006c9439 in ExecProcNode (node=0x26cd7f8) at
../../../src/include/executor/executor.h:241
#10 0x00000000006cbd73 in ExecutePlan (estate=0x26ccda0,
planstate=0x26cd7f8, use_parallel_mode=0 '\000', operation=CMD_SELECT,
sendTuples=1 '\001', numberTuples=0,
direction=ForwardScanDirection, dest=0x26b2ce0, execute_once=1
'\001') at execMain.c:1718
#11 0x00000000006c9a12 in standard_ExecutorRun (queryDesc=0x26d7fa0,
direction=ForwardScanDirection, count=0, execute_once=1 '\001') at
execMain.c:361
#12 0x00000000006c982e in ExecutorRun (queryDesc=0x26d7fa0,
direction=ForwardScanDirection, count=0, execute_once=1 '\001') at
execMain.c:304
#13 0x00000000006d096c in ParallelQueryMain (seg=0x26322a8,
toc=0x7fda24d46000) at execParallel.c:1271
#14 0x000000000053272d in ParallelWorkerMain (main_arg=1203628635) at
parallel.c:1149
#15 0x00000000007e8c99 in StartBackgroundWorker () at bgworker.c:841
#16 0x00000000007fc029 in do_start_bgworker (rw=0x2656d00) at postmaster.c:5741
#17 0x00000000007fc36b in maybe_start_bgworkers () at postmaster.c:5945
#18 0x00000000007fb3fa in sigusr1_handler (postgres_signal_arg=10) at
postmaster.c:5134
#19 <signal handler called>
#20 0x0000003dd26e1603 in __select_nocancel () at
../sysdeps/unix/syscall-template.S:82
#21 0x00000000007f6bee in ServerLoop () at postmaster.c:1721
#22 0x00000000007f63dd in PostmasterMain (argc=3, argv=0x2630180) at
postmaster.c:1365
#23 0x000000000072cb40 in main (argc=3, argv=0x2630180) at main.c:228

Thanks & Regards,
Rajkumar Raghuwanshi
QMG, EnterpriseDB Corporation