What is the job limit for Splunk?

In Splunk, the number of concurrent search jobs is governed by several configurable parameters, ensuring optimal performance and resource utilization. The primary factors influencing these limits include:

1. System-Wide Concurrent Searches

• Base Settings: Defined in the limits.conf file under the [search] stanza:

  • base_max_searches: Specifies the base number of concurrent searches allowed.
  • max_searches_per_cpu: Determines additional concurrent searches permitted per CPU core.

  The total number of concurrent searches is calculated as:

  base_max_searches + (number_of_CPU_cores * max_searches_per_cpu)
  

  For example, with base_max_searches set to 4, max_searches_per_cpu set to 1, and a system with 2 CPU cores:

  Total Concurrent Searches = 4 + (2 * 1) = 6
  

2. Role-Based Search Limits

• User-Level Limits: Configured in the authorize.conf file for each role:

  • srchJobsQuota: Maximum number of concurrent historical searches a user in the role can run.
  • rtSrchJobsQuota: Maximum number of concurrent real-time searches allowed per user in the role.

  These settings ensure that individual users or roles do not monopolize system resources.

3. Scheduled and Summarization Searches

• Scheduler Limits: The [scheduler] stanza in limits.conf manages scheduled searches:

  • max_searches_perc: Defines the percentage of total concurrent searches that can be allocated to scheduled searches.

  For instance, setting max_searches_perc to 50% means that half of the available concurrent searches can be used for scheduled tasks.

• Summarization Searches: These are searches generated for report acceleration or data model acceleration. Their concurrency limits are set as a percentage of the scheduled searches limit, ensuring they don't consume excessive resources.

4. Disk Usage Quotas

• Search Job Disk Quota: The srchDiskQuota parameter in authorize.conf specifies the maximum disk space (in MB) that a user's search jobs can consume. This prevents any single user from exhausting disk resources.

Conclusion

Splunk's architecture allows administrators to fine-tune the number of concurrent search jobs through system-wide settings, role-based configurations, and scheduler parameters. Adjusting these settings ensures efficient resource utilization and maintains system performance. It's essential to balance these configurations with the available hardware resources to prevent overloading the system.