DBI311

 Resource Governor – Feature Overview  Architecture Overview  “What”, “Why”, “How” of IO governance  What has Changed- XEvents, DMVs & PerfMon  Feature DEMO  Real-Time workload- TPC DEMO  Summary & Call to Action

Resource Governor was first introduced CPU and Memory governance Resource Governor- Feature Overview Affinity CPU_CAP_PERCENT IO Governance Feature Goals Minimize run-away queries Improve predictability of query execution

Attaining Balanced System 4 What is a balanced system? A system where most expensive resource can be leveraged to its maximum without any other components in the system bottlenecking it The five main components of a Balanced System Concept: Juergen Thomas Microsoft

Resource Governor Architecture 5 ……. Attributes

Why govern IOs?

What can be governed? SSAS SSISSSRS Yes Read I/O Write I/O (some caveats) Physical Reads Data Files No Internal Pool Logical Reads Log Files Future Improvements? Network I/O Better support for Hekaton (In-Memory)

ALTER RESOURCE GOVERNOR { DISABLE | RECONFIGURE } | WITH ( CLASSIFIER_FUNCTION = { schema_name.function_name | NULL } ) | RESET STATISTICS | WITH ( MAX_OUTSTANDING_IO_PER_VOLUME = value) [ ; ]

10 Newly added columns (sys.dm_resource_governor_resource_pools) min_iops_per_volume, Int, NullableThe Min IOPS per Volume setting for this Pool. Null if Pool is not governed for IO, i.e. Min=0, Max=INF max_iops_per_volume, Int, NullableThe Max IOPS per Volume setting for this Pool. Null if unlimited. read_ios_queued_total, Int, NullableThe total read IOs enqueued since we reset the RG statistics. read_ios_issued_total, Int, NullableThe total read IOs issued since we reset the RG statistics. read_ios_completed_total, Int, NotNullThe total read IOs completed since we reset the RG statistics. read_bytes_total, Bigint, NotNullThe total bytes read since we reset the RG statistics. read_io_stall_total_ms, Bigint, NullableTotal time between read IO issue and completion read_io_stall_queued_ms, Bigint, Nullable Total time between read IO arrival and completion. read_io_stall_queued_ms - read_io_stall_total_ms is the latency introduced because of IO resource governance.

Newly added DMV for IO Workload (sys.dm_resource_governor_resource_pool_volu mes) pool_id, Int, NotNullID of the resource pool volume_name, String, NotNullName of the disk volume read_ios_queued_total, Int, NullableThe total read IOs enqueued since we reset the RG statistics. read_ios_issued_total, Int, NullableThe total read IOs issued since we reset the RG statistics. read_ios_completed_total, Int, NotNullThe total read IOs completed since we reset the RG statistics. read_bytes_total, Bigint, NotNullThe total bytes read since we reset the RG statistics. read_io_stall_total_ms, Bigint, NullableTotal time between read IO issue and completion read_io_stall_queued_ms, Bigint, Nullable Total time between read IO arrival and completion. read_io_stall_queued_ms - read_io_stall_total_ms is the latency introduced because of IO resource governance.

12 XEvent Additions NameData file_read_enqueuedmode file_handle offset database_id file_id filegroup_id size path NameData file_write_enqueuedmode file_handle offset database_id file_id filegroup_id size path io_data

What has Changed- PerfMon 13 Disk Read IOs/secNumber of read operations from the disk in the last second Disk Read Bytes/secNumber of bytes read from the disk in the last second Avg. Disk Read IO (ms) Average time, in milliseconds, of a read operation from the disk Disk Write IOs/secNumber of write operations to the disk in the last second Disk Write Bytes/secNumber of bytes written to the disk in the last second Avg. Disk Write IO (ms) Average time, in milliseconds, of a write operation to the disk

Tricks MAX_OUTSTANDING_IO_PER_VOL UME There is no recommended value (max = 100). We suggest users to test the performance with different values (i.e. using SQLIO) CLASSIFIER function Should be in master Triggered at connect Tricks to efficiently utilize IO_PER_VOL

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