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.
Phase-1 of Kickstarter graphics - 1 Category: 2D Animation, Advertisement Design, Creative Design, Digital Art, Graphic Design, Illustration, Photoshop, Web Design Budget: $30 - $250 USD
12-Dec-2025 05:03 GMT
Shopify Automation for Beef Orders Category: API Integration, Automation, Email Marketing, HTML, Order Processing, Payment Processing, PHP, Shopify, Shopify Templates, Xero Budget: $250 - $750 AUD
12-Dec-2025 05:01 GMT
UI/UX Review & Enhancement for a simple Web App Category: Adobe XD, Figma, Graphic Design, Sketch, UI / User Interface, User Experience Research, User Interface / IA, UX / User Experience, Web Design Budget: $10 - $30 USD
12-Dec-2025 05:01 GMT
Magento E-Commerce Store Build Category: ECommerce, HTML, Magento, Magento 2, Payment Gateway Integration, Web Design, Web Development Budget: ₹100 - ₹400 INR
12-Dec-2025 05:00 GMT
Wooden Product Prototype 3D Modeling Category: 3D Animation, 3D CAD, 3D Design, 3D Graphic Design, 3D Modelling, 3D Printing, 3D Rendering, Solidworks Budget: $15 - $25 USD
12-Dec-2025 04:59 GMT
Athlete Social Media Manager Category: Content Creation, Facebook Marketing, Instagram, Marketing, Social Media Management, Social Media Marketing, Twitter, Video Editing Budget: $30 - $250 USD
12-Dec-2025 04:58 GMT
Professional Malay Writer Needed Category: Content Writing, Editing, English (US) Translator, Language Tutoring, Malay Translator, Proofreading, Simplified Chinese Translator, Tamil Translator, Translation Budget: $14 - $30 NZD
