Fix resource group memory overuse issue when increasing concurrency.

Resource group may have memory overuse in below case:

	CREATE RESOURCE GROUP rg_concurrency_test WITH
	(concurrency=1, cpu_rate_limit=20, memory_limit=60,
	 memory_shared_quota=0, memory_spill_ratio=10);
	CREATE ROLE role_concurrency_test RESOURCE GROUP rg_concurrency_test;

	11:SET ROLE role_concurrency_test;
	11:BEGIN;

	21:SET ROLE role_concurrency_test;
	22:SET ROLE role_concurrency_test;
	21&:BEGIN;
	22&:BEGIN;

	ALTER RESOURCE GROUP rg_concurrency_test SET CONCURRENCY 2;

	11:END;

The cause is that we didn't check overall memory quota usage in the
past, so pending queries can be waken up as long as the concurrency
limit is not reached, in such a case if the currently running tranctions
have used all the memory quota in the resource group then the overall
memory usage will be exceeded.

To fix this issue we now checks both concurrency limit and memory quota
usage to decide whether to wake up pending queries.
Signed-off-by: NZhenghua Lyu <zlv@pivotal.io>

src/backend/storage/lmgr/proc.c

@@ -374,6 +374,7 @@ InitProcess(void)
 	MyProc->waitProcLock = NULL;
 	MyProc->resWaiting = false;
 	MyProc->resGranted = false;
+	MyProc->resSlotId = -1;
 	for (i = 0; i < NUM_LOCK_PARTITIONS; i++)
 		SHMQueueInit(&(MyProc->myProcLocks[i]));
 

src/include/storage/proc.h

@@ -172,6 +172,7 @@ struct PGPROC
 	bool		resGranted;	/* true means a resource group slot is granted.
 							   false when wake up from a resource group which
 							   is locked for drop */
+	int			resSlotId;	/* the resource group slot id granted */
 };
 
 /* NOTE: "typedef struct PGPROC PGPROC" appears in storage/lock.h. */

src/include/utils/resgroup.h

@@ -25,6 +25,8 @@ extern int MaxResourceGroups;
 extern double gp_resource_group_cpu_limit;
 extern double gp_resource_group_memory_limit;
 
+struct ResGroupConfigSnapshot;
+
 /* Type of statistic infomation */
 typedef enum
 {
@@ -54,7 +56,8 @@ extern void AllocResGroupEntry(Oid groupId);
 extern void FreeResGroupEntry(Oid groupId);
 
 extern void SerializeResGroupInfo(StringInfo str);
-extern void DeserializeResGroupInfo(const char *buf, int len);
+extern void DeserializeResGroupInfo(struct ResGroupConfigSnapshot *config,
+									const char *buf, int len);
 
 extern bool ShouldAssignResGroupOnMaster(void);
 extern void AssignResGroupOnMaster(void);

src/test/isolation2/expected/resgroup_alter_concurrency.out

+-- create a resource group when gp_resource_manager is queue
+DROP ROLE IF EXISTS role_concurrency_test;
+DROP
+-- start_ignore
+DROP RESOURCE GROUP rg_concurrency_test;
+ERROR:  resource group "rg_concurrency_test" does not exist
+-- end_ignore
+CREATE RESOURCE GROUP rg_concurrency_test WITH (concurrency=1, cpu_rate_limit=20, memory_limit=60, memory_shared_quota=0, memory_spill_ratio=10);
+CREATE
+CREATE ROLE role_concurrency_test RESOURCE GROUP rg_concurrency_test;
+CREATE
+
+--
+-- increase concurrency after pending queries
+--
+
+ALTER RESOURCE GROUP rg_concurrency_test SET CONCURRENCY 1;
+ALTER
+
+11:SET ROLE role_concurrency_test;
+SET
+11:BEGIN;
+BEGIN
+
+21:SET ROLE role_concurrency_test;
+SET
+22:SET ROLE role_concurrency_test;
+SET
+21&:BEGIN;  <waiting ...>
+22&:BEGIN;  <waiting ...>
+
+ALTER RESOURCE GROUP rg_concurrency_test SET CONCURRENCY 2;
+ALTER
+
+SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+rsgname            |waiting_reason|current_query                                                     
+-------------------+--------------+------------------------------------------------------------------
+admin_group        |              |SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+rg_concurrency_test|              |<IDLE> in transaction                                             
+rg_concurrency_test|resgroup      |BEGIN;                                                            
+rg_concurrency_test|resgroup      |BEGIN;                                                            
+(4 rows)
+
+11:END;
+END
+11q: ... <quitting>
+
+SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+rsgname            |waiting_reason|current_query                                                     
+-------------------+--------------+------------------------------------------------------------------
+admin_group        |              |SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+rg_concurrency_test|              |<IDLE> in transaction                                             
+rg_concurrency_test|              |<IDLE> in transaction                                             
+(3 rows)
+
+21<:  <... completed>
+BEGIN
+22<:  <... completed>
+BEGIN
+21:END;
+END
+22:END;
+END
+21q: ... <quitting>
+22q: ... <quitting>
+
+SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+rsgname    |waiting_reason|current_query                                                     
+-----------+--------------+------------------------------------------------------------------
+admin_group|              |SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+(1 row)
+
+--
+-- increase concurrency before pending queries
+--
+
+ALTER RESOURCE GROUP rg_concurrency_test SET CONCURRENCY 1;
+ALTER
+
+11:SET ROLE role_concurrency_test;
+SET
+11:BEGIN;
+BEGIN
+
+ALTER RESOURCE GROUP rg_concurrency_test SET CONCURRENCY 2;
+ALTER
+
+21:SET ROLE role_concurrency_test;
+SET
+22:SET ROLE role_concurrency_test;
+SET
+21&:BEGIN;  <waiting ...>
+22&:BEGIN;  <waiting ...>
+
+SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+rsgname            |waiting_reason|current_query                                                     
+-------------------+--------------+------------------------------------------------------------------
+admin_group        |              |SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+rg_concurrency_test|              |<IDLE> in transaction                                             
+rg_concurrency_test|resgroup      |BEGIN;                                                            
+rg_concurrency_test|resgroup      |BEGIN;                                                            
+(4 rows)
+
+11:END;
+END
+11q: ... <quitting>
+
+SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+rsgname            |waiting_reason|current_query                                                     
+-------------------+--------------+------------------------------------------------------------------
+admin_group        |              |SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+rg_concurrency_test|              |<IDLE> in transaction                                             
+rg_concurrency_test|              |<IDLE> in transaction                                             
+(3 rows)
+
+21<:  <... completed>
+BEGIN
+22<:  <... completed>
+BEGIN
+21:END;
+END
+22:END;
+END
+21q: ... <quitting>
+22q: ... <quitting>
+
+SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+rsgname    |waiting_reason|current_query                                                     
+-----------+--------------+------------------------------------------------------------------
+admin_group|              |SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+(1 row)
+
+-- cleanup
+DROP ROLE role_concurrency_test;
+DROP
+DROP RESOURCE GROUP rg_concurrency_test;
+DROP

src/test/isolation2/expected/resgroup_concurrency.out

@@ -101,7 +101,7 @@ ALTER
 SELECT r.rsgname, num_running, num_queueing, num_queued, num_executed FROM gp_toolkit.gp_resgroup_status s, pg_resgroup r WHERE s.groupid=r.oid AND r.rsgname='rg_concurrency_test';
 rsgname            |num_running|num_queueing|num_queued|num_executed
 -------------------+-----------+------------+----------+------------
-rg_concurrency_test|3          |0           |1         |3           
+rg_concurrency_test|2          |1           |1         |2           
 (1 row)
 SELECT concurrency,proposed_concurrency FROM gp_toolkit.gp_resgroup_config WHERE groupname='rg_concurrency_test';
 concurrency|proposed_concurrency

src/test/isolation2/input/enable_resgroup.source

@@ -19,6 +19,7 @@
 ! bash /tmp/.resgroup_mem_helper.sh;
 ! rm -f /tmp/.resgroup_mem_helper.sh;
 ! gpconfig -c gp_resource_manager -v group;
+! gpconfig -c gp_resource_group_cpu_limit -v 0.9;
 ! gpstop -rai;
 -- end_ignore
 

src/test/isolation2/isolation2_resgroup_schedule

@@ -5,8 +5,12 @@ test: resgroup_syntax
 test: resgroup_transaction
 
 test: resgroup_concurrency
+test: resgroup_alter_concurrency
 test: resgroup_memory_statistic
 test: resgroup_memory_limit
+test: resgroup_cpu_rate_limit
+
+# memory spill tests
 test: resgroup_memory_hashagg_spill
 test: resgroup_memory_hashjoin_spill
 test: resgroup_memory_materialize_spill
@@ -14,6 +18,5 @@ test: resgroup_memory_sisc_mat_sort
 test: resgroup_memory_sisc_sort_spill
 test: resgroup_memory_sort_spill
 test: resgroup_memory_spilltodisk
-test: resgroup_cpu_rate_limit
 
 test: disable_resgroup

src/test/isolation2/output/enable_resgroup.source

@@ -42,6 +42,9 @@
 20170502:01:28:12:000367 gpconfig:sdw6:gpadmin-[WARNING]:-Managing queries with resource groups is an experimental feature. A work-in-progress version is enabled.
 20170502:01:28:13:000367 gpconfig:sdw6:gpadmin-[INFO]:-completed successfully
 
+! gpconfig -c gp_resource_group_cpu_limit -v 0.9;
+20170803:10:42:57:015929 gpconfig:nyu-vm-centos:gpadmin-[INFO]:-completed successfully
+
 ! gpstop -rai;
 -- end_ignore
 

src/test/isolation2/sql/resgroup_alter_concurrency.sql

+-- create a resource group when gp_resource_manager is queue
+DROP ROLE IF EXISTS role_concurrency_test;
+-- start_ignore
+DROP RESOURCE GROUP rg_concurrency_test;
+-- end_ignore
+CREATE RESOURCE GROUP rg_concurrency_test WITH
+(concurrency=1, cpu_rate_limit=20, memory_limit=60, memory_shared_quota=0, memory_spill_ratio=10);
+CREATE ROLE role_concurrency_test RESOURCE GROUP rg_concurrency_test;
+
+--
+-- increase concurrency after pending queries
+--
+
+ALTER RESOURCE GROUP rg_concurrency_test SET CONCURRENCY 1;
+
+11:SET ROLE role_concurrency_test;
+11:BEGIN;
+
+21:SET ROLE role_concurrency_test;
+22:SET ROLE role_concurrency_test;
+21&:BEGIN;
+22&:BEGIN;
+
+ALTER RESOURCE GROUP rg_concurrency_test SET CONCURRENCY 2;
+
+SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+
+11:END;
+11q:
+
+SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+
+21<:
+22<:
+21:END;
+22:END;
+21q:
+22q:
+
+SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+
+--
+-- increase concurrency before pending queries
+--
+
+ALTER RESOURCE GROUP rg_concurrency_test SET CONCURRENCY 1;
+
+11:SET ROLE role_concurrency_test;
+11:BEGIN;
+
+ALTER RESOURCE GROUP rg_concurrency_test SET CONCURRENCY 2;
+
+21:SET ROLE role_concurrency_test;
+22:SET ROLE role_concurrency_test;
+21&:BEGIN;
+22&:BEGIN;
+
+SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+
+11:END;
+11q:
+
+SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+
+21<:
+22<:
+21:END;
+22:END;
+21q:
+22q:
+
+SELECT rsgname,waiting_reason,current_query FROM pg_stat_activity;
+
+-- cleanup
+DROP ROLE role_concurrency_test;
+DROP RESOURCE GROUP rg_concurrency_test;