Hello,
I got the following error during DBT-3 benchmark with SF=20.
psql:query21.sql:50: ERROR: invalid memory alloc request size 1073741824
psql:query21.sql:50: ERROR: invalid memory alloc request size 1073741824
It looks to me Hash node tries to 1GB area using palloc0(), but it exceeds
the limitation of none-huge interface.
(gdb) bt
#0 0x00007f669d29a989 in raise () from /lib64/libc.so.6
#1 0x00007f669d29c098 in abort () from /lib64/libc.so.6
#2 0x000000000090ccfd in ExceptionalCondition (conditionName=0xb18130
"!(((Size) (size) <= ((Size) 0x3fffffff)))",
errorType=0xb17efd "FailedAssertion", fileName=0xb17e40 "mcxt.c",
lineNumber=856) at assert.c:54
#3 0x000000000093ad53 in palloc0 (size=1073741824) at mcxt.c:856
#4 0x0000000000673045 in ExecHashTableCreate (node=0x7f669de951f0,
hashOperators=0x24dbf90, keepNulls=0 '\000') at nodeHash.c:391
#5 0x00000000006752e1 in ExecHashJoin (node=0x24d74e0) at nodeHashjoin.c:169
#6 0x000000000065abf4 in ExecProcNode (node=0x24d74e0) at execProcnode.c:477
#7 0x0000000000681026 in ExecNestLoop (node=0x24d6668) at nodeNestloop.c:123
#8 0x000000000065abca in ExecProcNode (node=0x24d6668) at execProcnode.c:469
#9 0x0000000000681026 in ExecNestLoop (node=0x24d61f8) at nodeNestloop.c:123
#10 0x000000000065abca in ExecProcNode (node=0x24d61f8) at execProcnode.c:469
#11 0x0000000000681026 in ExecNestLoop (node=0x24d5478) at nodeNestloop.c:123
#12 0x000000000065abca in ExecProcNode (node=0x24d5478) at execProcnode.c:469
#13 0x0000000000681026 in ExecNestLoop (node=0x24d51d0) at nodeNestloop.c:123
#14 0x000000000065abca in ExecProcNode (node=0x24d51d0) at execProcnode.c:469
The attached patch replaces this palloc0() by MemoryContextAllocHuge() +
memset().
Indeed, this hash table is constructed towards the relation with
nrows=119994544,
so, it is not strange even if hash-slot itself is larger than 1GB.
Another allocation request potentially reset of expand hash-slot may also needs
to be "Huge" version of memory allocation, I think.
Thanks,
Below is the query itself and EXPLAIN result.
--------------------------------------------------------------------
dbt3c=# EXPLAIN VERBOSE
dbt3c-# select
dbt3c-# s_name,
dbt3c-# count(*) as numwait
dbt3c-# from
dbt3c-# supplier,
dbt3c-# lineitem l1,
dbt3c-# orders,
dbt3c-# nation
dbt3c-# where
dbt3c-# s_suppkey = l1.l_suppkey
dbt3c-# and o_orderkey = l1.l_orderkey
dbt3c-# and o_orderstatus = 'F'
dbt3c-# and l1.l_receiptdate > l1.l_commitdate
dbt3c-# and exists (
dbt3c(# select
dbt3c(# *
dbt3c(# from
dbt3c(# lineitem l2
dbt3c(# where
dbt3c(# l2.l_orderkey = l1.l_orderkey
dbt3c(# and l2.l_suppkey <> l1.l_suppkey
dbt3c(# )
dbt3c-# and not exists (
dbt3c(# select
dbt3c(# *
dbt3c(# from
dbt3c(# lineitem l3
dbt3c(# where
dbt3c(# l3.l_orderkey = l1.l_orderkey
dbt3c(# and l3.l_suppkey <> l1.l_suppkey
dbt3c(# and l3.l_receiptdate > l3.l_commitdate
dbt3c(# )
dbt3c-# and s_nationkey = n_nationkey
dbt3c-# and n_name = 'UNITED KINGDOM'
dbt3c-# group by
dbt3c-# s_name
dbt3c-# order by
dbt3c-# numwait desc,
dbt3c-# s_name
dbt3c-# LIMIT 100;
QUERY PLAN
--------------------------------------------------------------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------------------------------------------------------------------------
------------------
Limit (cost=6792765.24..6792765.24 rows=1 width=26)
Output: supplier.s_name, (count(*))
-> Sort (cost=6792765.24..6792765.24 rows=1 width=26)
Output: supplier.s_name, (count(*))
Sort Key: (count(*)) DESC, supplier.s_name
-> HashAggregate (cost=6792765.22..6792765.23 rows=1 width=26)
Output: supplier.s_name, count(*)
Group Key: supplier.s_name
-> Nested Loop Anti Join (cost=4831094.94..6792765.21 rows=1
width=26)
Output: supplier.s_name
-> Nested Loop (cost=4831094.37..6792737.52 rows=1
width=34)
Output: supplier.s_name, l1.l_suppkey, l1.l_orderkey
Join Filter: (supplier.s_nationkey =
nation.n_nationkey)
-> Nested Loop (cost=4831094.37..6792736.19 rows=1
width=38)
Output: supplier.s_name, supplier.s_nationkey,
l1.l_suppkey, l1.l_orderkey
-> Nested Loop (cost=4831093.81..6792728.20
rows=1 width=42)
Output: supplier.s_name,
supplier.s_nationkey, l1.l_suppkey, l1.l_orderkey, l2.l_orderkey
Join Filter: (l1.l_suppkey =
supplier.s_suppkey)
-> Hash Semi Join
(cost=4831093.81..6783870.20 rows=1 width=12)
Output: l1.l_suppkey,
l1.l_orderkey, l2.l_orderkey
Hash Cond: (l1.l_orderkey =
l2.l_orderkey)
Join Filter: (l2.l_suppkey <>
l1.l_suppkey)
-> Index Scan using
lineitem_l_orderkey_idx_part1 on public.lineitem l1 (cost=0.57..1847781.73 rows
=39998181 width=8)
Output: l1.l_orderkey,
l1.l_partkey, l1.l_suppkey, l1.l_linenumber, l1.l_quantity, l1.l_extende
dprice, l1.l_discount, l1.l_tax, l1.l_returnflag, l1.l_linestatus,
l1.l_shipdate, l1.l_commitdate, l1.l_receiptdate, l1.l_shipinstruct, l1.l_shipm
ode, l1.l_comment
-> Hash
(cost=3331161.44..3331161.44 rows=119994544 width=8)
Output: l2.l_orderkey,
l2.l_suppkey
-> Seq Scan on
public.lineitem l2 (cost=0.00..3331161.44 rows=119994544 width=8)
Output: l2.l_orderkey,
l2.l_suppkey
-> Seq Scan on public.supplier
(cost=0.00..6358.00 rows=200000 width=34)
Output: supplier.s_suppkey,
supplier.s_name, supplier.s_address, supplier.s_nationkey, supplier.s_pho
ne, supplier.s_acctbal, supplier.s_comment
-> Index Scan using
orders_o_orderkey_o_orderdate_idx on public.orders (cost=0.56..7.98 rows=1
width=4)
Output: orders.o_orderkey,
orders.o_custkey, orders.o_orderstatus, orders.o_totalprice, orders.o_orderdate,
orders.o_orderpriority, orders.o_clerk, orders.o_shippriority, orders.o_comment
Index Cond: (orders.o_orderkey =
l1.l_orderkey)
Filter: (orders.o_orderstatus =
'F'::bpchar)
-> Seq Scan on public.nation (cost=0.00..1.31
rows=1 width=4)
Output: nation.n_nationkey, nation.n_name,
nation.n_regionkey, nation.n_comment
Filter: (nation.n_name = 'UNITED
KINGDOM'::bpchar)
-> Index Scan using lineitem_l_orderkey_idx_part1 on
public.lineitem l3 (cost=0.57..13.69 rows=89 width=8)
Output: l3.l_orderkey, l3.l_partkey, l3.l_suppkey,
l3.l_linenumber, l3.l_quantity, l3.l_extendedprice, l3.l_discount, l
3.l_tax, l3.l_returnflag, l3.l_linestatus, l3.l_shipdate, l3.l_commitdate,
l3.l_receiptdate, l3.l_shipinstruct, l3.l_shipmode, l3.l_comment
Index Cond: (l3.l_orderkey = l1.l_orderkey)
Filter: (l3.l_suppkey <> l1.l_suppkey)
(41 rows)
--
NEC Business Creation Division / PG-Strom Project
KaiGai Kohei <kai...@ak.jp.nec.com>
--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers
