Application Performance Optimization

Optimize end-to-end application performance — database queries, HTTP pipelines, serialization, and monitoring in production.

45 min•By Priygop Team•Last updated: Feb 2026

Database Performance

EF Core Query Optimization: Use AsNoTracking() for read-only queries, AsSplitQuery() for queries with multiple includes, compiled queries for hot paths
Pagination: Always paginate large result sets — use keyset pagination (WHERE id > @lastId ORDER BY id LIMIT 20) instead of OFFSET/FETCH for large datasets
N+1 Problem: Use Include/ThenInclude to eager-load related data — or use projection (Select) to fetch only needed columns
Raw SQL / Dapper: Use for complex reporting queries — Dapper is 10-20x faster than EF Core for read-heavy queries with no change tracking overhead
Database Indexing: Create indexes for WHERE, JOIN, and ORDER BY columns — use EXPLAIN ANALYZE to verify query plans. Remove unused indexes
Connection Pooling: Configure pool size based on concurrent requests — too few pools create wait times, too many exhaust database connections

Try It Yourself: LINQ Explorer

Try It Yourself: LINQ ExplorerHTML

HTML Editor

✓ ValidTab = 2 spaces

<!DOCTYPE html>
<html><head><style>
body{font-family:Arial,sans-serif;padding:20px;background:#1e1e2e;color:#cdd6f4}
h2{color:#89b4fa}.card{background:#313244;padding:20px;border-radius:10px;max-width:550px}
pre{background:#1e1e2e;padding:12px;border-radius:8px;font-size:13px;border:1px solid #45475a;line-height:1.5}
button{background:#89b4fa;color:#1e1e2e;border:none;padding:8px 16px;border-radius:6px;cursor:pointer;font-weight:bold;margin:4px}
</style></head><body>
<div class="card"><h2>LINQ Query Explorer</h2>
<button onclick="show(0)">Where + Select</button>
<button onclick="show(1)">GroupBy</button>
<button onclick="show(2)">Aggregate</button>
<pre id="code"></pre></div>
<script>
var codes=["// Filter and transform
var expensive = products
    .Where(p => p.Price > 100)
    .Select(p => new {p.Name, p.Price})
    .OrderBy(p => p.Price)
    .ToList();","// Group by category
var grouped = products
    .GroupBy(p => p.Category)
    .Select(g => new {
        Category = g.Key,
        Count = g.Count(),
        Avg = g.Average(p => p.Price)
    });","// Aggregates
var stats = new {
    Total = products.Sum(p => p.Price),
    Avg = products.Average(p => p.Price),
    Max = products.Max(p => p.Price),
    Min = products.Min(p => p.Price),
    Count = products.Count()
};"];
function show(i){document.getElementById("code").textContent=codes[i];}
show(0);
</script></body></html>

<!DOCTYPE html>
<html><head><style>
body{font-family:Arial,sans-serif;padding:20px;background:#1e1e2e;color:#cdd6f4}
h2{color:#89b4fa}.card{background:#313244;padding:20px;border-radius:10px;max-width:550px}
pre{background:#1e1e2e;padding:12px;border-radius:8px;font-size:13px;border:1px solid #45475a;line-height:1.5}
button{background:#89b4fa;color:#1e1e2e;border:none;padding:8px 16px;border-radius:6px;cursor:pointer;font-weight:bold;margin:4px}
</style></head><body>
<div class="card"><h2>LINQ Query Explorer</h2>
<button onclick="show(0)">Where + Select</button>
<button onclick="show(1)">GroupBy</button>
<button onclick="show(2)">Aggregate</button>
<pre id="code"></pre></div>
<script>
var codes=["// Filter and transform
var expensive = products
    .Where(p => p.Price > 100)
    .Select(p => new {p.Name, p.Price})
    .OrderBy(p => p.Price)
    .ToList();","// Group by category
var grouped = products
    .GroupBy(p => p.Category)
    .Select(g => new {
        Category = g.Key,
        Count = g.Count(),
        Avg = g.Average(p => p.Price)
    });","// Aggregates
var stats = new {
    Total = products.Sum(p => p.Price),
    Avg = products.Average(p => p.Price),
    Max = products.Max(p => p.Price),
    Min = products.Min(p => p.Price),
    Count = products.Count()
};"];
function show(i){document.getElementById("code").textContent=codes[i];}
show(0);
</script></body></html>

Result

Click ▶ Run to see the result

Edit the code on the left, then click Run

HTML|36 lines|1397 chars|✓ Valid syntax

UTF-8

Quick Quiz — .NET Performance

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