Expected duration: 1 - 2 weeks I am facing a critical issue with my WordPress website hosted on a dedicated Kinsta server. Every time I send email campaigns via ConvertKit, the server experiences a significant spike in errors (500, 502, 503 & 525), leading to downtime and disrupted user experiences. This issue is persistent despite multiple attempts to address it with Kinsta support, and I need expert help to resolve it.
BACKGROUND -> Hosting: Dedicated Kinsta server (C2-standard-8) with 8 CPUs, 32GB RAM, and 20 PHP workers. -> Emails: Weekly campaigns to ~40,000 subscribers through ConvertKit.
Error Details: -> Errors predominantly occur immediately after an email campaign is sent. -> High traffic spikes from email tracking links (with query strings like ck_subscriber_id and utm_ parameters) overwhelm the server. -> Admin-ajax requests appear to be a contributing factor. -> Disabling caching for ck_subscriber_id cookies may be causing conflicts when combined with UTM parameters.
Additional details: -> Code snippet plugin previously caused errors (now resolved by deactivating it). -> Ongoing PHP worker and cron job timeouts have been reported in the logs. -> There is a large spike in cache MISS status when emails are sent. -> Attached is a chat thread with Kinsta providing fuller details. -> Here is an example of the URL string from our newsletter - https://www.conservation-careers.com/job/conservation-detection-nosework-seminar-2025/?utm_source=convertkit&utm_medium=email&utm_campaign=Unmissable%20opportunities%20in%20Conservation%20this%20week%20-%2015873629
OBJECTIVES Root Cause Analysis: -> Investigate the server logs, performance, caching and traffic behaviour during email campaigns. -> Identify specific conflicts or configurations causing the errors.
Optimization & Fixes: -> Resolve any issues identified in the Root Cause Analysis. This may include the following, -> Addressing conflicts between caching rules, UTM parameters, and ck_subscriber_id. -> Optimizing admin-ajax usage to reduce server load. -> Implementing efficient caching rules for email campaign links.
Testing & Monitoring: -> Monitor server performance during the next email campaign to confirm the issue is resolved. -> Provide a detailed report of changes implemented.
Recommendations: -> Suggest further performance improvements for WordPress on Kinsta hosting. -> Propose preventative measures for scalability during high-traffic periods.
Past Kinsta support actions: -> Temporarily disabled caching rules for ck_subscriber_id. -> Recommended enabling pre-caching for campaign URLs. -> Restarted PHP and adjusted NGINX settings to handle traffic better.
Deliverables: -> A detailed report of the issue and resolution steps. -> Implementation and validation of fixes to prevent recurrence. -> Recommendations for improving server performance and handling high traffic.
Requirements: -> Proven experience with WordPress performance optimization, particularly on Kinsta hosting. -> Familiarity with ConvertKit and handling query string conflicts in email tracking. -> Strong analytical and troubleshooting skills, especially with PHP worker management, caching, and admin-ajax optimization. -> Clear communication and ability to document solutions.
If you can help resolve this issue and enhance my server’s performance, please provide a brief outline of your approach and relevant experience.
Princess Cruise Employment Verification, Princess Cruise lines Category: Customer Service, Data Management, Data Protection, Documentation, Human Resources, Project Management, Recruitment, Report Writing, Time Management, Word Processing Budget: $10 - $50 USD
14-Jan-2026 17:04 GMT
Employment History Verification, melomed pyt holdings Category: Customer Service, Data Collection, Data Entry, Data Management, Documentation, Human Resources, Interviewing, Report Writing, Research, Time Management Budget: $10 - $50 USD
14-Jan-2026 17:02 GMT
Advanced E-commerce Website Development Category: API Integration, Content Management System (CMS), ECommerce, HTML, Payment Gateway Integration, PHP, Web Development, Web Design Budget: ₹37500 - ₹75000 INR
Ortho & Dental Job Verification, Ortho and Dental Category: Customer Service, Data Analysis, Data Entry, Data Management, Recruitment, Report Writing, Research, Time Management, Word Processing Budget: $10 - $50 USD
14-Jan-2026 17:00 GMT
Residential Loan Originator & Client Lead Category: CRM, Customer Service, Internet Marketing, Lead Generation, Leads, Marketing, Real Estate, Sales Budget: $8 - $15 USD
Verify Dr. Ross Employment History, Dr. Reza Ross Category: Audit, Data Entry, Data Management, Documentation, Email Handling, Phone Support, Project Management, Report Writing, Research, Time Management Budget: $10 - $50 USD
Florida Wind Stamp for Shed Category: Architectural Engineering, Construction Engineering, Structural Engineering Budget: $250 - $750 USD
14-Jan-2026 16:55 GMT
TikTok Product Demo Videos Category: Adobe Premiere Pro, After Effects, CapCut, Final Cut Pro, Motion Graphics, Video Editing, Video Production, Video Services Budget: $10 - $100 USD
14-Jan-2026 16:55 GMT
Cancer Specialty Hospital Project in Guwahati Category: 3D Rendering, 3D Visualization, Architecture, AutoCAD, Building Architecture, Building Design, Building Information Modeling, Interior Design, Photoshop, Rhino 3D Budget: ₹12500 - ₹37500 INR
14-Jan-2026 16:53 GMT
Tally Audit Data Analysis Support Category: Accounting, Business Analysis, Data Analysis, Finance, Financial Analysis, Financial Research, Inventory Management, Ratio Analysis Budget: ₹1500 - ₹12500 INR
14-Jan-2026 16:52 GMT
Amazon India Market Research for SkinCare Launch Category: Amazon Product Launch, Business Development, Competitor Analysis, Covers & Packaging, Data Analytics, Internet Marketing, Market Research, Product Management, Product Sourcing Budget: ₹1500 - ₹12500 INR
