your HTTP request connection start duration too long
If your HTTP request connection start duration is taking more than 7 seconds, here are some possible causes and troubleshooting steps:
Possible Causes:
- Network Latency – Slow internet or network congestion.
- DNS Resolution Delay – Slow DNS lookup affecting the connection initiation.
- Proxy or VPN Issues – Additional routing causing delays.
- Server Response Delay – The destination server is slow to respond.
- TCP Handshake Delay – Slow three-way handshake due to network or server issues.
- TLS/SSL Handshake Delay – Issues with SSL negotiation.
- High System Load – If the client machine is overloaded, connections may take longer.
- Firewall or Security Software – Could be inspecting or delaying the request.
Troubleshooting Steps:
1. Check Network Latency
Run the following command to check latency to the target server:
ping <server-ip>
If response times are high, network congestion or routing issues could be the cause.
2. Perform a Traceroute
To check where the delay occurs:
traceroute <server-ip> # Linux/macOS tracert <server-ip> # Windows
This helps identify if the issue is at the client, ISP, or server level.
3. Measure DNS Resolution Time
Test DNS lookup speed:
nslookup <server-url>
or
dig <server-url>
If it's slow, try using a faster DNS provider like Google (8.8.8.8) or Cloudflare (1.1.1.1).
4. Test Connection Time with curl
Check how long each phase of the request takes:
curl -o /dev/null -s -w "DNS Lookup: %{time_namelookup}\nTCP Handshake: %{time_connect}\nSSL Handshake: %{time_appconnect}\nTransfer Start: %{time_starttransfer}\nTotal Time: %{time_total}\n" https://your-url.com
This will help you pinpoint whether the delay is in DNS, TCP, SSL, or response time.
5. Check for Proxy or VPN Issues
- If using a proxy or VPN, disable it and test again.
- If behind a corporate proxy, check its logs for delays.
6. Optimize TLS/SSL Handshake
- If using HTTPS, check SSL negotiation time with:
openssl s_client -connect <server-url>:443 -debug
- Ensure the server supports modern ciphers and TLS 1.2+ for faster handshakes.
7. Increase Connection Pooling (for Java, Spring, etc.)
If you're using a Java application, enable HTTP connection pooling to reduce repeated handshakes:
PoolingHttpClientConnectionManager cm = new PoolingHttpClientConnectionManager(); cm.setMaxTotal(100); // Set max connections CloseableHttpClient httpClient = HttpClients.custom().setConnectionManager(cm).build();
8. Debug with Wireshark or TCPDump
Capture packets to analyze network delays:
tcpdump -i eth0 host <server-ip>
Or use Wireshark to inspect TCP handshake and SSL negotiation.
Next Steps:
- If the issue is with the server, optimize server response times.
- If network-related, switch networks (e.g., mobile hotspot) and test again.
- If using a cloud service (e.g., AWS, Azure), check their status pages for outages.