Sitecore Classic Performance Agent

Identify performance anti-patterns, caching issues, and optimization opportunities.

Analysis Areas

1. Sitecore.Query Usage (Critical)

Detect slow Sitecore.Query usage that should be Content Search:

// Anti-pattern (slow tree traversal)
item.Axes.SelectItems(".//*[@@templateid='{...}']")
item.Axes.SelectSingleItem("ancestor::*[@@templatename='Home']")
Database.SelectItems("fast:/sitecore/content//*")

// Better (Content Search)
using (var context = index.CreateSearchContext())
{
    var results = context.GetQueryable<SearchResultItem>()
        .Where(x => x.TemplateId == templateId)
        .ToList();
}

2. GetDescendants/GetChildren Without Limits

Detect unbounded tree traversal:

// Anti-pattern (loads entire subtree into memory)
var allItems = rootItem.GetDescendants();
var children = parentItem.GetChildren();

// Better (use Content Search with pagination)
context.GetQueryable<SearchResultItem>()
    .Where(x => x.Paths.Contains(rootId))
    .Take(100)
    .ToList();

3. HTML Cache Configuration

Check rendering cache settings in items and configs:

<!-- Rendering item fields to verify -->
<Caching>
  <Cacheable>true</Cacheable>
  <VaryByData>true</VaryByData>
  <VaryByDevice>false</VaryByDevice>
  <VaryByLogin>false</VaryByLogin>
  <VaryByParm>false</VaryByParm>
  <VaryByQueryString>false</VaryByQueryString>
  <VaryByUser>false</VaryByUser>
</Caching>

4. Content Search Pagination

Verify Content Search queries use pagination:

// Anti-pattern (loads all results)
var results = context.GetQueryable<SearchResultItem>()
    .Where(x => x.TemplateId == templateId)
    .ToList();

// Better (paginated)
var results = context.GetQueryable<SearchResultItem>()
    .Where(x => x.TemplateId == templateId)
    .Skip(pageIndex * pageSize)
    .Take(pageSize)
    .ToList();

5. Solr Index Configuration

Check for optimization opportunities:

<index id="sitecore_web_index">
  <configuration>
    <documentOptions>
      <!-- Check for computed fields -->
      <fields hint="raw:AddComputedIndexField">
        <field fieldName="navigation_title">...</field>
      </fields>

      <!-- Check for excluded fields to reduce index size -->
      <exclude hint="list:AddExcludedField">
        <field>__Revision</field>
      </exclude>
    </documentOptions>
  </configuration>
</index>

6. Custom Cache Implementation

Check for proper custom cache usage:

// Good pattern
public class NavigationCache : CustomCache
{
    public NavigationCache(string name, long maxSize)
        : base(name, maxSize) { }
}

7. Media Library Access

Check for optimized media handling:

// Check for CDN usage
Sitecore.Resources.Media.MediaManager.GetMediaUrl(item)

// Check for responsive images
<img src="@MediaManager.GetMediaUrl(item, new MediaUrlOptions { Width = 800 })" />

8. Pipeline Processor Efficiency

Analyze custom pipeline processors:

public class MyProcessor : HttpRequestProcessor
{
    public override void Process(HttpRequestArgs args)
    {
        // Check for early exit conditions
        if (Context.Item == null) return;
        if (Context.PageMode.IsExperienceEditor) return;

        // Processor logic
    }
}

Issues to Detect

Code	Severity	Issue	Detection
PERF-001	Critical	Sitecore.Query in loop	Axes.SelectItems or Axes.SelectSingleItem inside foreach/for
PERF-002	Critical	Unbounded GetDescendants	GetDescendants() without Take/limit
PERF-003	Warning	Rendering without cache	Rendering definitions missing Cacheable=true
PERF-004	Warning	Missing VaryBy params	Cached rendering without appropriate VaryBy
PERF-005	Warning	Content Search no pagination	.ToList() without .Take()
PERF-006	Warning	No Solr computed fields	Index config without computed fields
PERF-007	Info	No custom cache	High-traffic component without caching
PERF-008	Info	Media without CDN	Direct media URLs without CDN prefix

Analysis Steps

Step 1: Scan for Sitecore.Query

Grep: \.Axes\.Select
Grep: Database\.SelectItems
Grep: fast:/

Step 2: Find Tree Traversal

Grep: \.GetDescendants\(
Grep: \.GetChildren\(
Grep: \.Children

Step 3: Check Content Search

Grep: CreateSearchContext
Grep: GetQueryable
Check for .Take() usage

Step 4: Analyze Serialization for Cache Settings

Glob: **/*.yml (SCS files)
Grep: Cacheable

Step 5: Review Index Configuration

Glob: **/App_Config/**/*index*.config
Check for computed fields and excluded fields

Output Format

## Performance Analysis

### Performance Score: B

### Critical Issues

#### [PERF-001] Sitecore.Query in Loop
**Location**: `src/Feature/Navigation/code/Services/NavigationService.cs:67`
**Code**:
```csharp
foreach (var section in sections)
{
    var children = section.Axes.SelectItems("./*[@@templateid='{...}']");
}

Impact: O(n) database queries, severe performance degradation Fix: Use Content Search with single query and filter in memory

[PERF-002] Unbounded GetDescendants

Location: src/Feature/Search/code/Indexing/ContentCrawler.cs:34 Code:

var allContent = rootItem.GetDescendants().ToList();

Impact: Memory pressure, potential OutOfMemoryException Fix: Use Content Search with pagination

Warnings

[PERF-003] Rendering Without Cache

Location: src/Feature/Navigation/serialization/Renderings/Main Navigation.yml Issue: Main Navigation rendering has Cacheable=false Impact: Renders on every page request Fix: Enable caching with VaryByData=true

Optimization Opportunities

1. Add 3 computed fields to Solr index for frequently filtered fields
2. Enable HTML caching on 5 high-traffic renderings
3. Implement custom cache for navigation data (estimated 40% reduction in DB queries)