Avoiding Limits Breaches

Slide deck from London Salesforce Developers talk on Salesforce limits and how to avoid breaching them.

Transcript

1. Nobody Beats the Governor Proactive Limits Management
2. Independent Salesforce specialist CTA MVP HoF 18 years Salesforce About me 18 years hitting limits
3. Limits primer Developing inside limits Monitoring limits Limit tracker Agenda
4. Limits Primer
5. Limits Primer What are limits in Salesforce? Runtime constraints Applied by the platform Transaction exceeding limits is terminated Why have limits? Protect the multi-tenant environment
6. Types of Limits Platform 500 object sharing rules per object Edition 200 custom objects in Enterprise License Concurrent long running Apex requests 10 (<=1000 licenses) - 50 (>=5000) Time window API calls per 24 hour period
7. Types of Limits Apex Transaction Limits (Governor Limits) SOQL queries - 100 (200 async) SOQL rows - 50,000 (50,000 async) DML statements - 150 (150 async) DML rows - 10,000 (10,000 async) CPU time - 10,000 msec (60,000 async) Heap size - 6Mb (12Mb async)
8. Rage against the limit? Limits are a good thing! Ensures fair use of shared resources Reduces risk of abuse Ensures consistent performance Encourages scalable solutions Requires efficient development
9. Developing inside limits
10. SOQL/DML in loops Query executed for every Opportunity May query same Account repeatedly Limit 100 Opportunities System.LimitException: Too many SOQL queries: 101
11. SOQL/DML in loops Bulkified One query, regardless of Opportunity count Limit 50,000 Accounts System.LimitException: Too many query rows: 50001
12. SOQL/DML in loops
13. Unfiltered Queries
14. Unfiltered Queries
15. Inefficient Code Excessive object creation Consumes heap Retrieving more records than you need Consumes heap Repeatedly querying the same records Consumes SOQL queries Complex logic Consumes CPU
16. Big O Notation Time complexity - worst case runtime growth of an algorithm
17. Nested Loops O(n*m) growth 10 Accounts 20 Contacts 200 Iterations 20 Accounts 40 Contacts 800 Iterations 200 Accounts 400 Contacts 80,000 Iterations 2,000 Accounts 4.000 Contacts 8,000,000 Iterations
18. Nested Loops O(n+m) growth 10 Accounts 20 Contacts 30 Iterations (200) 20 Accounts 40 Contacts 60 Iterations (800) 200 Accounts 400 Contacts 600 Iterations (80,000) 2,000 Accounts 4.000 Contacts 6,000 Iterations (8,000,000)
19. Additional Automation Bulk Insert Before Trigger After Trigger After Save Record Triggered Flow
20. Certified managed packages get their own set of limits For most per-transaction limits Limits apply per namespace Cross namespace limit 11 times default limit 1,100 SOQL queries 1,650 DML statements Managed Packages Doesn’t apply to ❌ Heap space ❌ CPU time No visibility into logic
21. Going Async Bulkified One query, regardless of Opportunity count Limit 50,000 Accounts System.LimitException: Too many query rows: 50001
22. Limit 50 million records Going Async
23. Going Async - Challenges Trade immediacy for scale User has to wait for result Uncertain timing Complicates error handling Separate transactions - partial success Data consistency/race conditions
24. Developing inside Limits
25. Monitoring Limits
26. Monitoring Limits
27. The Limit Lifecycle Test with current volumes Test with estimated growth Limit consumption increase Limits breach Panic! Fix Forget about limits
28. Debug Logs
29. Administration overhead Possible truncation Performance overhead Compliance Relies on luck Debug Logs - Challenges
30. Unit Tests
31. Unit Tests
32. Process Execute tests Retrieve log file Extract limit information Write to Salesforce Add automation Off platform - e.g. CLI Unit Tests Capture limits from tests
33. Shortened execution flow Test limitations E.g. Invoke execute() method once in batch apex test No integrations May involve mocks Indicative data Unit Tests - Challenges
34. Embedded Apex Code Consumes the limits you are tracking!
35. Platform Events
36. Sent immediately Information captured even if transaction fails Separate limit allocation If published immediately Processed in separate transaction Action without impacting tracking Delivered in order Impact if tracking platform event limits Platform Events
37. Limit Tracker
38. Limit Tracker Event Bus Apex Trigger Platform Event Platform Event Limit Tracker Snapshot Notifier Notifier Notifier Other Automation
39. Github Repository bobbuzz.me.uk/LimitTracker
40. Thank you!