Issue: memory_limit (default or set to 0) option definition confusing
Given:
MEMORY_LIMIT integer
The percentage of Greenplum Database memory resources to reserve for this resource
group. The minimum memory percentage for a resource group is 0. The maximum is 100.
The default value is 0.
When MEMORY_LIMIT is 0, Greenplum Database reserves no memory for the resource
group, but uses global shared memory to fulfill all memory requests in the group. If
MEMORY_LIMIT is 0, MEMORY_SPILL_RATIO must also be 0.
Practical:
memory_limit set to 0 means unlimited as per bellow Error.
CREATE RESOURCE GROUP rgroup2 WITH (CPU_RATE_LIMIT=5);
fifthposition
commented
3 years ago
Page No 945
Issue: memory_limit (default or set to 0) option definition confusing
Given: MEMORY_LIMIT integer The percentage of Greenplum Database memory resources to reserve for this resource group. The minimum memory percentage for a resource group is 0. The maximum is 100. The default value is 0. When MEMORY_LIMIT is 0, Greenplum Database reserves no memory for the resource group, but uses global shared memory to fulfill all memory requests in the group. If MEMORY_LIMIT is 0, MEMORY_SPILL_RATIO must also be 0.
Practical: memory_limit set to 0 means unlimited as per bellow Error.
CREATE RESOURCE GROUP rgroup2 WITH (CPU_RATE_LIMIT=5);
gpadmin=# SELECT * FROM gp_toolkit.gp_resgroup_config where groupname ='rgroup2' ; groupid | groupname | concurrency | cpu_rate_limit | memory_limit | memory_shared_quota | memory_spill_ratio | memory_auditor | cpuset ---------+---------------+-------------+----------------+--------------+---------------------+--------------------+----------------+-------- 115988 | rgroup2 | 20 | 5 | 0 | 80 | 0 | vmtracker | -1
gpadmin=# ALTER RESOURCE GROUP rgroup2 SET memory_spill_ratio 95; ERROR: when memory_limit is unlimited memory_spill_ratio must be set to 0 gpadmin=#