[Postgres-xc-bugs] get coredump when i create table in coordinator restore mode

[<xu...@cm...>]

Hi
In coordinator restore mode. I get coredump when client issue DDL  


Recreate steps:
1.pg_ctl start -Z restoremode -D /rdbdata/bcrdb_data/coord
2.psql -hzhcx5i -p20015 cxdb
3.create table:

   CREATE TABLE cm_busi_handle_201301 (
   so_nbr bigint,
   region_code integer,
   process_id integer,
   process_result integer,
   handle_seq integer,
   op_id integer,
   oper_date timestamp without time zone,
   oper_end_date timestamp without time zone,
   invoice_no character varying(20),
   property character varying(20),
   oper_desc text
   )
   DISTRIBUTE BY MODULO (region_code)
   TO NODE (datanode1,datanode2,datanode3,datanode4,datanode5,datanode6,datanode7,datanode8)

4.get coredump
 
  cxdb=# CREATE TABLE cm_busi_handle_201301 (
  cxdb(# so_nbr bigint,
  cxdb(# region_code integer,
  cxdb(# process_id integer,
  cxdb(# process_result integer,
  cxdb(# handle_seq integer,
  cxdb(# op_id integer,
  cxdb(# oper_date timestamp without time zone,
  cxdb(# oper_end_date timestamp without time zone,
  cxdb(# invoice_no character varying(20),
  cxdb(# property character varying(20),
  cxdb(# oper_desc text
  cxdb(# )
  cxdb-# DISTRIBUTE BY MODULO (region_code)
  cxdb-# TO NODE (datanode1,datanode2,datanode3,datanode4,datanode5,datanode6,datanode7,datanode8);
  The connection to the server was lost. Attempting reset: Failed.
  !>

5.stack when get coredump

gdb /rdbdata/bcrdb_install/bin/postgres /tmp/corefile/core.postgres.48524
(gd bt
#0  0x00000036a48328a5 in raise () from /lib64/libc.so.6
#1  0x00000036a4834085 in abort () from /lib64/libc.so.6
#2  0x00000036a486fa37 in __libc_message () from /lib64/libc.so.6
#3  0x00000036a4875366 in malloc_printerr () from /lib64/libc.so.6
#4  0x00000036a4877e93 in _int_free () from /lib64/libc.so.6
#5  0x0000000000769879 in AllocSetDelete (context=<value optimized out>) at aset.c:551
#6  0x0000000000769dad in MemoryContextDelete (context=0x12231e8) at mcxt.c:193
#7  0x000000000076aa70 in PortalDrop (portal=0x122d0c0, isTopCommit=<value optimized out>) at portalmem.c:588
#8  0x000000000067ddaa in exec_simple_query (
    query_string=0x114c1e0 "CREATE TABLE cm_busi_handle_201301 (\n    so_nbr bigint,\n    region_code integer,\n    process_id integer,\n    process_result integer,\n    handle_seq integer,\n    op_id integer,\n    oper_date timestamp "...) at postgres.c:1149
#9  0x000000000067f82f in PostgresMain (argc=<value optimized out>, argv=<value optimized out>, dbname=0x1166708 "cxdb", 
    username=<value optimized out>) at postgres.c:4243
#10 0x000000000063b84a in BackendRun (argc=<value optimized out>, argv=<value optimized out>) at postmaster.c:4202
#11 BackendStartup (argc=<value optimized out>, argv=<value optimized out>) at postmaster.c:3891
#12 ServerLoop (argc=<value optimized out>, argv=<value optimized out>) at postmaster.c:1702
#13 PostmasterMain (argc=<value optimized out>, argv=<value optimized out>) at postmaster.c:1369
#14 0x00000000005d1420 in main (argc=4, argv=0x1131c70) at main.c:206

My analysis is as below：
   when I start coordinator in restoremode. Pooler process is not running. So NumDataNodes is zero. 
   so there is a problem in function BuildRelationDistributionNodes 

   {

    //In restoremode. NumDataNodes is 0. So memory allocation has the problem. when the parameter of palloc0 is 0.Then palloc0 allocate smallest chunk to                //nodeoids. If we need more memory, there is a memory overflow. so when postgres free memory, get coredump
 
      nodeoids = (Oid ) palloc0(NumDataNodes * sizeof(Oid)); 
 

   }
   

The right code as follows:

BuildRelationDistributionNodes(List *nodes, int *numnodes)
{
  Oid *nodeoids;
  ListCell *item;

  *numnodes = 0;
  int numdatanotes;
  numdatanotes=list_length(nodes);
  nodeoids = (Oid *) palloc0(numdatanotes*sizeof(Oid));
  
}

In my team, Test result is ok. Please review these code, If any problem. Please let me know.


xu...@cm...