8 Sharded Database
This chapter provides information about the Sharded Database metrics.
Sharding is a data tier architecture in which data is horizontally partitioned across independent databases. Each database is hosted on a dedicated server with its own local resources - CPU, memory, flash, or disk, and each database in such a configuration is called a shard. All the shards together make up a single logical database, which is referred to as a sharded database (SDB).
Shard Director
This section provides information about the metric categories available for the Shard Director target.
Shard Director is a Global Service Manager, which supports the routing of connections based on data location.
Global Service Performance
This section provides information on the metrics in the Global Service Performance category.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Every 15 minutes |
| Metric Name | Description | Unit |
|---|---|---|
| Average Response Time | Elapsed time per user call. | Milliseconds |
| CPU IO Violations | Count of CPU IO threshold violations. | None |
| CPU Load | CPU utilization | Percentage |
| Calls Per Second | Number of logins, parses, or execute calls per second during the sample period. | None |
| Collected Region | Name of the GSM region. | None |
| Latency | Network latency between database region and GSM region. | Milliseconds |
| Latency Region | Name of the GSM region for which latency is computed. | None |
| Master | Global Master GSM | None |
| Region Master | Regional Master GSM | None |
| Runtime Load Balance | Percentage of workload for runtime load balancing purposes. | None |
| Session Count | Current session count over the past 30 seconds. | None |
Load
This section provides information on the metrics in the Load category.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Every 5 minutes |
| Metric Name | Description | Unit |
|---|---|---|
| Connections Established (per min) | Count of connections established per minute. | None |
| Connections Refused (per min) | Count of connections refused per minute. | None |
General Status
This section provides information on the metrics in the General Status category.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Every 5 minutes |
| Metric Name | Description | Unit |
|---|---|---|
| Host | GSM host | None |
| Port | GSM port | None |
| Region | Region name | None |
| Region Master | Regional master GSM | None |
| Start Date | GSM start time | Date |
| TNSPING Response Time | Response time of TNSPING test from GDS home to GSM server. | Milliseconds |
| TNSPING Status | Status of TNSPING test from GDS home to GSM server. | Status (0 or 1) |
Shard Global Service Performance
The metrics in this category report the shard global service performance details.
Note that this metric is disabled by default and you can enable it in the Oracle Enterprise Manager console or using a Monitoring template.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Every 15 minutes |
| Metric Name | Description | Unit |
|---|---|---|
| Average Active Sessions | Ratio of the DB time to wall clock time. | None |
| Service Time (m/s) | Average time spent per user call. | Milliseconds |
| Throughput (calls/sec) | Number of user calls per second. | Operations per second |
Chunk Performance
The metric in this category reports the chunk-level performance.
Note that this metric is disabled by default and you can enable it in the Oracle Enterprise Manager console or using a Monitoring template.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Every 15 minutes |
| Metric Name | Description | Unit |
|---|---|---|
| Throughput (calls/sec) | Number of calls per second in a chunk. | Operations per second |
Response
The metric in this category reports the status of the Sharded Database.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Event-driven |
| Metric Name | Description | Unit |
|---|---|---|
| Status | Status of the Sharded Database. | None |
Service Distribution
The metrics in this category report the service distribution details.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Every 5 minutes |
| Metric Name | Description | Unit |
|---|---|---|
| Calls per second distribution (Instance:::Database:::Region) | Number of calls distribution per service per shard database per region. | Operations per second |
| Region Name | Name of the region. | None |
| Response time distribution (Instance:::Database:::Region) | Response time distribution per service per shard database per region. | Milliseconds |
Service Status
The metrics in this category report the service status details.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Every 5 minutes |
| Metric Name | Description | Unit |
|---|---|---|
| Preferred Database(s) | Preferred list of instances where the service should run. If the role is specified to a service, then all role matching instances are preferred. | None |
| Running Database(s) | Instances where the service is running. | None |
| Status | Status of the global service based on running and
preferred instances.
|
None |
Shard Chunk Size (GB)
The metric in this category reports the size of a chunk per shard.
Note that this metric is disabled by default and you can enable it in the Oracle Enterprise Manager console or using a Monitoring template.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Every 15 minutes |
| Metric Name | Description | Unit |
|---|---|---|
| Chunk Size (GB) | Size of a chunk per shard. | GB |
Shard Size (GB)
The metrics in this category report the allocated size of the shard.
Note that this metric is disabled by default and you can enable it in the Oracle Enterprise Manager console or using a Monitoring template.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Every 15 minutes |
| Metric Name | Description | Unit |
|---|---|---|
| Number of Chunks Change Rate | Rate of change in the number of chunks per shard during metric collection. | Percentage |
| Data Size Change Rate | Rate of change in data size per shard during metric collection. | Percentage |
| Data Size (GB) | Size of a shard. | GB |
| Number of Chunks | Number of chunks per shard. | None |
| Number of Tablespaces | Number of tablespaces per shard. | None |
Shard Status Details
The metrics in this category report shard status details.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Every 15 minutes |
| Metric Name | Description | Unit |
|---|---|---|
| Connect String | Shard database connect string used in the Shard Director (GSM) configuration. | None |
| Convert State | Displays shard database role change possibility. | None |
| DDL Error | Displays DDL error in GSM operations, if any. | None |
| DDL Number | DDL operation number in GSM. | None |
| Data Guard Broker ID | Data guard broker ID shared across the primary and standby databases. | None |
| Database Status | Status of the shard database in GSM. | None |
| Database Type | Shard database type. For example, RAC or Non-RAC. | None |
| Database Up | Status of the shard database in Oracle Enterprise Manager. | None |
| Deployment Status | Deployment status of the shard database from the GSM. For example, Deployed or Pending. | None |
| Host | Shard database host. | None |
| Is Primary | Shard database role. | None |
| Oracle Home | Oracle home path for the shard database. | None |
| Region Name | Region in which the shard database is deployed. | None |
| Shardgroup Name | Name of the shardgroup to which the shard database belongs. | None |
| Shardspace Name | Name of the shardspace to which the shard database belongs. | None |
Shard Tablespace Summary
The metrics in this category report the shard tablespace summary.
Note that this metric is disabled by default and you can enable it in the Oracle Enterprise Manager console or using a Monitoring template.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Every 15 minutes |
| Metric Name | Description | Unit |
|---|---|---|
| Tablespace Set Name | Tablespace set name. | None |
| Chunk Number | ID of the chunk. | None |
| Shardspace ID | ID of the shardspace. | None |
Unique Keys Count
The metrics in this category report the details of the unique sharding keys per shard.
Note that this metric is disabled by default and you can enable it in the Oracle Enterprise Manager console or using a Monitoring template.
| Target Version | Evaluation and Collection Frequency |
|---|---|
| 12c and later | Every 1 hour |
| Metric Name | Description | Unit |
|---|---|---|
| Number of Unique Keys Change Rate | Rate of change of the number of unique keys per shard during metric collection. | Percentage |
| Unique Keys Count | Number of unique sharding keys present in the shard. | None |