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.
Modern Electronics Webshop Design Category: Adobe XD, Figma, Graphic Design, HTML, UI / User Interface, User Interface / IA, Web Design Budget: $250 - $750 USD
22-Feb-2026 23:00 GMT
Strategi TikTok Raup 5 Juta Category: Article Writing, Catch Phrases, Content Strategy, Digital Marketing, Internet Marketing, Slogans, Social Media Marketing, Video Production Budget: $15 - $25 USD
Online Category: ECommerce, HTML, Mobile App Development, Payment Gateway Integration, SEO, Shopping Cart Integration, Web Development, Web Design, WooCommerce, WordPress Budget: $750 - $1500 USD
22-Feb-2026 22:57 GMT
Penjelasan Fitur Aplikasi Manajemen Category: Business Writing, Comedy Writing, Content Writing, Copywriting, Documentation, Marketing, Project Management, Romance Writing, Technical Writing, User Experience Research Budget: $15 - $25 USD
22-Feb-2026 22:55 GMT
Advocate for Universal Human Rights -- 4 Category: Conflict Resolution, Fundraising, Legal Research, Public Speaking, Social Impact, Speech Writing, Training, Writing Budget: £250 - £750 GBP
22-Feb-2026 22:50 GMT
Arabic to English translator needed Category: Arabic Translator, Editing, English (UK) Translator, English (US) Translator, English Translation, Legal Translation, Translation, Word Processing Budget: €8 - €30 EUR
International B2B SEO Overhaul Category: B2B Marketing, Content Strategy, Google Analytics, Internet Marketing, Keyword Research, Link Building, Search Engine Marketing (SEM), SEO Budget: $10 - $30 USD
22-Feb-2026 22:48 GMT
Resolve solve Error on IrishBestDeal.com Category: Apache, CMS, Database Administration, Nginx, PHP, SEO, Web Development, Website Management, Website Optimization, WordPress Budget: €8 - €30 EUR
22-Feb-2026 22:48 GMT
Ulasan Teknis Smartphone Mendalam Category: Article Writing, Blog Writing, Content Writing, Copywriting, Editing, Research Writing, SEO Writing, Technical Writing Budget: $250 - $750 USD
22-Feb-2026 22:46 GMT
Drone Photographer Category: Cinematography, Content Creation, Drone Photography, Drones, Photography, Video Editing, Video Production Budget: $250 - $750 USD
22-Feb-2026 22:45 GMT
Teen Swahili Language Learning Materials Category: Creative Writing, Educational Research, Language Tutoring, Swahili Translator, Teaching / Lecturing Budget: $250 - $750 USD
