---
id: 3742d47e-51ad-4c21-8a76-c7f8b910d5ea
---

# High Apache Request Time to First Byte (TTFB) Incident
---

The High Apache Request Time to First Byte (TTFB) Incident is a type of incident related to web server performance. It occurs when there is a significant delay in the time it takes for the server to respond to a request from a client. TTFB is a metric that measures the time it takes for a web server to send the first byte of data in response to a request. When TTFB is high, it can indicate that the server is experiencing performance issues or that there is a problem with the network connection. This type of incident can impact website performance, user experience, and ultimately, customer satisfaction.

### Parameters
```shell
export SERVER_IP="PLACEHOLDER"

export URL="PLACEHOLDER"

export OLD_VALUE="PLACEHOLDER"

export NEW_VALUE="PLACEHOLDER"
```

## Debug

### Check Apache status
```shell
systemctl status apache2
```

### Check the Apache error logs for any relevant errors
```shell
tail -n 100 /var/log/apache2/error.log | grep -i error
```

### Check the Apache access logs for any requests that have a high TTFB
```shell
tail -n 100 /var/log/apache2/access.log | awk '{if($NF>0.5) print $0}'
```

### Check network connection between client and server
```shell
traceroute ${SERVER_IP}
```

### Check server resource usage
```shell
top
```

### Check disk usage
```shell
df -h
```

### Check memory usage
```shell
free -m
```

### Check server response time for a specific URL
```shell
curl -w "Total time: %{time_total}\n" -o /dev/null -s ${URL}
```

## Repair

### Optimize Apache server configuration: This can involve tweaking settings such as the number of worker threads or processes, adjusting the KeepAliveTimeout value, and increasing the number of concurrent requests that the server can handle.
```shell


#!/bin/bash



# Stop the Apache server

sudo service apache2 stop



# Update the number of worker threads or processes

sudo sed -i 's/${OLD_VALUE}/${NEW_VALUE}/g' /etc/apache2/mods-enabled/mpm_prefork.conf



# Update the KeepAliveTimeout value

sudo sed -i 's/${OLD_VALUE}/${NEW_VALUE}/g' /etc/apache2/apache2.conf



# Update the number of concurrent requests that the server can handle

sudo sed -i 's/${OLD_VALUE}/${NEW_VALUE}/g' /etc/apache2/apache2.conf



# Start the Apache server

sudo service apache2 start


```

The High Apache Request Time to First Byte (TTFB) Incident is a type of incident related to web server performance. It occurs when there is a significant delay in the time it takes for the server to respond to a request from a client. TTFB is a metric that measures the time it takes for a web server to send the first byte of data in response to a request. When TTFB is high, it can indicate that the server is experiencing performance issues or that there is a problem with the network connection. This type of incident can impact website performance, user experience, and ultimately, customer satisfaction.


This incident type refers to an increase in the number of errors per second on a Tomcat server, which could indicate an issue with the server itself, the host, a deployed application, or an application servlet. This could include errors generated when the Tomcat server runs out of memory, can't find a requested file or servlet, or is unable to serve a JSP due to syntax errors in the servlet codebase. This incident type requires immediate attention to diagnose and address the underlying issue.


Increase of the errors/second rate for Tomcat server

This incident type typically refers to a situation where there is an anomaly in the Tomcat max processing time on a host. The maximum amount of time it takes for the server to process one request, from the time an available thread starts processing the request to the time it returns a response, has exceeded the expected threshold. This could indicate that a JSP page isn’t loading or an associated process (such as a database query) is taking too long to complete.


Anomalous max processing time for Tomcat host

A Host CPU high iowait incident occurs when the CPU iowait is greater than 10%, indicating that the system is disk or network bound. This can cause performance issues and may require investigation to identify the root cause and resolve the issue.


Host CPU high iowait incident.

This incident type occurs when the response time of the backend for a specific host in the HAProxy load balancing software exceeds 500 milliseconds. This can be an indication of a performance issue or bottleneck in the system that requires investigation and resolution to prevent further impact.


HAProxy Backend response time is above 500ms for host.

This incident type refers to a security vulnerability in the SSL/TLS configuration of the Apache HTTP Server, which can leave the server and its users vulnerable to attacks. The SSL/TLS configuration is responsible for encrypting the communication between the server and its clients, and if it is not configured properly, it can be exploited by hackers to intercept or modify sensitive data. This type of incident requires immediate attention from software engineers to ensure that the SSL/TLS configuration is properly configured to prevent any potential security threats.


Inadequate SSL/TLS Configuration for Apache HTTP Server.

```shell
export SERVER_IP="PLACEHOLDER"

export URL="PLACEHOLDER"

export OLD_VALUE="PLACEHOLDER"

export NEW_VALUE="PLACEHOLDER"
```


### Check Apache status

```shell
systemctl status apache2
```

### Check the Apache error logs for any relevant errors

```shell
tail -n 100 /var/log/apache2/error.log | grep -i error
```

### Check the Apache access logs for any requests that have a high TTFB

```shell
tail -n 100 /var/log/apache2/access.log | awk '{if($NF>0.5) print $0}'
```

### Check network connection between client and server

```shell
traceroute ${SERVER_IP}
```

### Check server resource usage

```shell
top
```

### Check disk usage

```shell
df -h
```

### Check memory usage

```shell
free -m
```

### Check server response time for a specific URL

```shell
curl -w "Total time: %{time_total}\n" -o /dev/null -s ${URL}
```


### Optimize Apache server configuration: This can involve tweaking settings such as the number of worker threads or processes, adjusting the KeepAliveTimeout value, and increasing the number of concurrent requests that the server can handle.

```shell


#!/bin/bash



# Stop the Apache server

sudo service apache2 stop



# Update the number of worker threads or processes

sudo sed -i 's/${OLD_VALUE}/${NEW_VALUE}/g' /etc/apache2/mods-enabled/mpm_prefork.conf



# Update the KeepAliveTimeout value

sudo sed -i 's/${OLD_VALUE}/${NEW_VALUE}/g' /etc/apache2/apache2.conf



# Update the number of concurrent requests that the server can handle

sudo sed -i 's/${OLD_VALUE}/${NEW_VALUE}/g' /etc/apache2/apache2.conf



# Start the Apache server

sudo service apache2 start


```


High Apache Request Time to First Byte (TTFB) Incident

Overview

Parameters

Debug

Check Apache status

Check the Apache error logs for any relevant errors

Check the Apache access logs for any requests that have a high TTFB

Check network connection between client and server

Check server resource usage

Check disk usage

Check memory usage

Check server response time for a specific URL

Repair

Optimize Apache server configuration: This can involve tweaking settings such as the number of worker threads or processes, adjusting the KeepAliveTimeout value, and increasing the number of concurrent requests that the server can handle.

Learn more

Related Runbooks

Increase of the errors/second rate for Tomcat server

Anomalous max processing time for Tomcat host

Host CPU high iowait incident.

HAProxy Backend response time is above 500ms for host.

Support