ArcGIS Server records various service statistics, such as total requests, average response time, and timeouts, and reports this information in ArcGIS Server Manager as one or a series of graphs. Administrators and publishers can use this information to monitor service activity to better understand how clients are using services. For example, monitoring server statistics helps you answer questions such as the following:
- What is the total number of requests that my ArcGIS Server site handled during the past week?
- How was the service request load distributed during the past month?
- How are my services performing on an hourly basis?
- What was the maximum number of service instances used at any given time for a particular service?
Role of server statistics
Statistics are an important tool for monitoring service usage. They help you identify how clients use your services and identify potential issues that may affect your services. Statistics also represent a history of events that occur over time.
For example, an administrator may create a report of the maximum response times for all services in the site over the past month. Upon examining the report, the administrator can correlate a spike in response times from a specific service to complaints from clients. Using this information, the administrator can increase the number of instances used by that service to help decrease response times.
Access to server statistics
Use ArcGIS Server Manager to access, view, configure, and delete reports generated from server statistics. Manager aggregates the various statistics from the site and presents the information in a graph that is easy to view and manipulate. For multiple-machine ArcGIS Server sites, statistics presented in Manager are aggregated for the whole site; to view statistics for an individual machine, use the ArcGIS Server Administrator Directory, as discussed below.
See Work with server statistics for full instructions on using Manager to view statistics.
Statistics are stored in the ArcGIS Server system directory. This directory is also used to manage information necessary for maintaining services, GIS servers, and database connections, as well as storing files uploaded to the ArcGIS Server site. Do not manually modify or delete files in this directory. There can only be one instance of this directory within the ArcGIS Server site.
To allocate ample space for statistics information stored in the system directory, consider each of the following specifications:
- Aggregation interval (default interval is 30 minutes). This determines the granularity at which statistics are generated. When decreasing this interval, for example, to 5 minutes, the server will generate more statistics and in turn require a larger amount of disk space to store them. By contrast, when increasing the interval, fewer logs will be written, requiring less disk space.
- Statistics retention interval (default interval is unlimited days). Specifying a shorter time frame, for example, 30 days, can prevent the statistics files from growing larger than expected.
- The number of services participating in a site.
For example, the recommended storage allotment for the following scenario based on an average-size ArcGIS Server site would be at least 500 MB of disk space:
- Aggregation interval set to the default = (30 minutes)
- Statistics retention interval set to 3 years = (1,095 days)
- Fifty services participating in the site, 90 percent of which are continuously active
Keep in mind that larger organizations with many services may require well over 500 MB of disk space.
For more information and instructions for configuring server statistics, see Working with server statistics.
Advanced monitoring of server statistics
If you're an advanced user of ArcGIS Server, you can monitor server statistics through the ArcGIS REST API. The API allows you to programmatically derive statistics over time. You can also view statistics for an individual machine in a multiple-machine ArcGIS Server site, as opposed to the aggregate view given by Manager.
You can also use the ArcGIS Server Administrator Directory to learn how to send a request to ArcGIS Server and work with a response.