Certainly! In Splunk, the search mode determines how much data is processed and displayed during a search. The three search modes are Fast, Smart, and Verbose. Each mode offers a different balance between performance and the level of detail in the search results.

Differences Between Fast Mode, Smart Mode, and Verbose Mode

1. Fast Mode

• Purpose: Optimizes search speed by limiting data processing.
• Features:
  • Field Extraction: Only default fields are extracted (e.g., _time, host, source, sourcetype, index).
  • Event Data: Minimal event information is processed.
  • Search Results: Focuses on returning statistical results or data that doesn't require full event details.
• Benefits:
  • Performance: Searches run faster due to reduced processing.
  • Efficiency: Ideal for large datasets when you need quick insights.
• Use Cases:
  • When running reports or dashboards that rely on statistical aggregations.
  • When detailed event information is not necessary.

2. Smart Mode

• Purpose: Balances performance and data detail by automatically adjusting field extraction based on the search type.
• Features:
  • Adaptive Field Extraction:
  • Transforming Searches: For searches using transforming commands (e.g., stats, chart), Splunk limits field extraction to improve speed.
  • Non-Transforming Searches: For searches without transforming commands, more fields are extracted to provide detailed event information.
  • Event Data: Provides a moderate amount of event detail.
• Benefits:
  • Flexibility: Automatically optimizes searches based on context.
  • Balanced Performance: Offers a compromise between speed and detail.
• Use Cases:
  • Default mode suitable for most searches.
  • When unsure about the necessary level of detail.

3. Verbose Mode

• Purpose: Provides complete event processing, extracting all possible fields.
• Features:
  • Full Field Extraction: All fields, including indexed and calculated fields, are extracted and available.
  • Event Data: Full event details are processed and displayed.
• Benefits:
  • Comprehensive Data: Ideal for in-depth analysis and troubleshooting.
  • Visibility: Access to all extracted fields for maximum insight.
• Drawbacks:
  • Performance Impact: Searches may run slower due to increased processing.
• Use Cases:
  • When you need detailed event information.
  • For debugging complex searches or exploring new data.

How to See and Change Search Modes in Splunk

Accessing Search Modes

1. Open the Search & Reporting App:

   • Log in to Splunk and navigate to the Search & Reporting app.

2. Locate the Search Mode Selector:

   • Under the search bar, on the right side, you'll see the current search mode indicated (e.g., Smart Mode).
   • 

3. Change the Search Mode:

   • Click on the mode indicator to open a dropdown menu.
   • Select Fast Mode, Smart Mode, or Verbose Mode as needed.

Observing Differences Between Modes

Example Scenario

Suppose you're running the following search:

index="web_logs" status=404

In Fast Mode

• Field Extraction:
  • Only default fields are available in the Fields sidebar.
  • Custom fields are not extracted.
• Event Data:
  • Events display minimal information.
• Performance:
  • The search completes quickly.

In Smart Mode

• Field Extraction:
  • If no transforming commands are used, more fields are extracted compared to Fast Mode.
  • If transforming commands are present, field extraction is limited to improve performance.
• Event Data:
  • Moderate level of detail is available.
• Performance:
  • Search speed is balanced with data detail.

In Verbose Mode

• Field Extraction:
  • All possible fields are extracted, including those defined by FIELDALIAS, REPORT, or EXTRACT in props.conf.
• Event Data:
  • Full event information is displayed.
• Performance:
  • Searches may take longer due to the extra processing required.

Comparing Search Results

• Fields Sidebar:

  • In Verbose Mode, the Fields sidebar will list many more fields than in Fast Mode.
  • You can expand each field to see its values and event distribution.

• Event Viewer:

  • In Verbose Mode, clicking on an event will show all extracted fields.
  • In Fast Mode, only default fields are visible.

Using the Job Inspector to Analyze Performance

1. Run a Search in Different Modes:

   • Execute the same search in Fast, Smart, and Verbose modes.

2. Access the Job Inspector:

   • After the search completes, click on the Job dropdown menu.
   • Select Inspect Job.

3. Review Search Performance:

   • The Job Inspector displays detailed metrics about the search execution.
   • Compare the Execution costs and Search job properties between modes.

Recommendations for Using Search Modes

• Use Fast Mode:

  • When you need quick results.
  • For searches that rely on indexed fields and do not require detailed event data.

• Use Smart Mode:

  • As the default for most searches.
  • When you want Splunk to optimize the search automatically.

• Use Verbose Mode:

  • When troubleshooting or exploring new data.
  • If you need access to all extracted fields and full event details.

Additional Tips

• Switching Modes During Analysis:

  • Start in Fast Mode for quick insights.
  • Switch to Verbose Mode if you need more detail.

• Customizing Field Extraction:

  • In Verbose Mode, you can see all fields to help build more efficient searches.

• Impact on Dashboard Performance:

  • Using Fast Mode in dashboards can improve loading times.
  • Verbose Mode may slow down dashboard performance due to increased processing.

Summary

Understanding the differences between Fast, Smart, and Verbose modes in Splunk helps you optimize your searches:

• Fast Mode: Prioritizes speed by limiting field extractions.
• Smart Mode: Balances performance and detail based on the search commands used.
• Verbose Mode: Provides full detail with all fields extracted, useful for deep analysis.

By selecting the appropriate search mode for your needs, you can improve search performance and get the right level of data detail for your analysis.

ADDITIONAL NOTES

Certainly! Demonstrating the difference between Smart Mode and Verbose Mode in Splunk can help you understand how each mode affects field extraction, event processing, and search performance. Below is a step-by-step guide to illustrate these differences using a practical example.

Objective: To observe how Smart Mode and Verbose Mode differ in terms of field extraction and search results.

Prerequisites

• Access to Splunk's Search & Reporting app.
• Some indexed data to search through, preferably with multiple fields and sourcetypes.

Step-by-Step Demonstration

Step 1: Choose a Search Query

We'll use a simple search that retrieves events from a specific index and sourcetype. For this example:

index="your_index" sourcetype="your_sourcetype"

Replace "your_index" and "your_sourcetype" with the actual index and sourcetype available in your Splunk environment.

Alternatively, you can use a general search:

index=_internal

This uses Splunk's internal logs, which are available in all Splunk installations.

Step 2: Run the Search in Smart Mode

1. Ensure Search Mode is Set to Smart Mode:

   • In the Search & Reporting app, look for the search mode selector beneath the search bar on the right side.
   • Click on it and select Smart Mode.

2. Execute the Search:

   • Enter your chosen search query.
   • Run the search by clicking the Search button or pressing Enter.

3. Observe the Results:

   • Fields Sidebar:
     • In Smart Mode, Splunk automatically extracts fields based on the search.
     • You should see a list of Interesting Fields on the left sidebar, which includes frequently occurring fields.
   • Event Data:
     • Click on an event to expand it.
     • Observe the extracted fields and their values.

4. Note the Performance:

   • Take note of the search completion time displayed at the top of the search results.

Step 3: Run the Same Search in Verbose Mode

1. Switch to Verbose Mode:

   • Click on the search mode selector again.
   • Select Verbose Mode.

2. Execute the Same Search:

   • Run the search with the same query as before.

3. Observe the Results:

   • Fields Sidebar:
     • In Verbose Mode, Splunk extracts all possible fields, including those defined by field extractions and field aliases.
     • You should see a larger number of fields listed under Interesting Fields and Selected Fields.
   • Event Data:
     • Expand an event.
     • Notice that more fields are extracted and displayed compared to Smart Mode.

4. Note the Performance:

   • Compare the search completion time to that of Smart Mode.
   • Typically, searches in Verbose Mode take longer due to the additional processing required for field extraction.

Step 4: Compare Field Extraction

• Number of Fields:

  • Smart Mode: Extracts a subset of fields relevant to the search, balancing performance and detail.
  • Verbose Mode: Extracts all possible fields, providing maximum detail.

• Field Availability:

  • Fields that were not present or visible in Smart Mode may now be available in Verbose Mode.

Step 5: Analyze Search Performance

• Access Job Inspector (optional for deeper analysis):

  1. Click on the Job dropdown menu near the search bar.
  2. Select Inspect Job.
  3. In the Job Inspector window, compare metrics such as Execution Costs and Search Pipeline between Smart Mode and Verbose Mode.

• Observations:

  • Smart Mode may show lower execution costs due to less field extraction.
  • Verbose Mode may have higher costs and longer duration due to comprehensive field extraction.

Step 6: Run a Transforming Search

To further illustrate the differences, run a transforming search that uses commands like stats or timechart.

Example Search:

index="your_index" sourcetype="your_sourcetype" | stats count by host

• In Smart Mode:

  • Splunk limits field extraction since transforming commands are used.
  • Only necessary fields for the transformation are extracted.

• In Verbose Mode:

  • Splunk still extracts all fields despite the transforming command.
  • This can lead to longer search times.

Step 7: Observe the Impact on Data Visualization

• Field Values and Charts:
  • In Verbose Mode, additional fields may be available for use in data visualizations or further analysis.
  • In Smart Mode, some fields may not be available, potentially limiting the detail in charts or reports.

Conclusion

By following these steps, you can clearly see the differences between Smart Mode and Verbose Mode in Splunk:

• Smart Mode:

  • Balances performance and detail.
  • Automatically adjusts field extraction based on the search.
  • Suitable for most searches where default field extraction is sufficient.

• Verbose Mode:

  • Provides comprehensive field extraction.
  • May impact search performance due to increased processing.
  • Ideal for deep-dive analyses, troubleshooting, or when you need access to all possible fields.

Understanding these differences helps you choose the appropriate search mode for your needs, optimizing both performance and the level of detail required for your analysis.

Additional Tips:

• When to Use Each Mode:

  • Smart Mode: Use for general searches where you need a balance of performance and detail.
  • Verbose Mode: Use when you need to see all extracted fields, such as during initial data exploration or troubleshooting.

• Switching Modes:

  • You can switch between modes at any time to see how the results and performance are affected.

• Customizing Field Extractions:

  • If certain fields are not available in Smart Mode but you need them, consider adjusting field extraction settings or using fields commands to include specific fields.