AWS Free Tier EC2 Usage

### 1. **AWS Management Console**
– **Log in to your AWS Management Console.**
– **Navigate to the EC2 Dashboard**:
– Select **Instances** from the left sidebar.
– Find your instance and select it to view its details.

– **Monitor CPU Usage**:
– Click on the **Monitoring** tab to see metrics like CPU Utilization, Network In/Out, Disk Read/Write, etc.
– You can set the time range for the graphs to get a better view of usage over specific periods.

– **Check Storage Usage**:
– To check the space usage of your EBS volumes, go to the **Elastic Block Store (EBS)** section in the left sidebar.
– Select **Volumes** and find the volume attached to your instance.
– The size of the volume is displayed, but to see how much space is actually used, you'll need to connect to the instance via SSH and check the disk usage using commands.

### 2. **Using SSH to Check Disk Usage**
1. Connect to your EC2 instance using SSH:

ssh -i your-key.pem ubuntu@your-instance-public-dns

2. Use the `df` command to check disk usage:

df -h

This command will show you the total space, used space, and available space on your filesystems.

3. For detailed CPU usage, you can use tools like `top` or `htop`:
– Install `htop` if it's not already installed:

sudo apt update
     sudo apt install htop

– Run `htop`:

htop

This tool gives you a real-time overview of CPU usage and other system resources.

### 3. **AWS CLI**
If you prefer using the command line, you can check usage with the AWS CLI:

– **Install and configure AWS CLI** if you haven't already.
– Use the following command to get CPU usage metrics:

aws cloudwatch get-metric-statistics --metric-name CPUUtilization --start-time 2024-12-01T00:00:00Z --end-time 2024-12-01T23:59:59Z --period 300 --namespace AWS/EC2 --statistics Average --dimensions Name=InstanceId,Value=your-instance-id

– To check your EBS usage, you'll still need to connect to the instance as described earlier.

### Note
The AWS Free Tier allows you to use certain resources for free, but usage beyond the specified limits may incur charges. Always monitor your usage to avoid unexpected costs.

### Disk Usage Summary
– **Root Filesystem (`/dev/root`)**
– **Total Size:** 6.8 GB
– **Used:** 3.4 GB
– **Available:** 3.4 GB
– **Usage Percentage:** 50%

– **Temporary Filesystems (tmpfs)**
– **/dev/shm:** 458 MB total, 0 MB used, 458 MB available (0% used)
– **/run:** 183 MB total, 932 KB used, 182 MB available (1% used)
– **/run/lock:** 5.0 MB total, 0 MB used, 5.0 MB available (0% used)
– **/run/user/1000:** 92 MB total, 12 KB used, 92 MB available (1% used)

– **EFI Variables Filesystem (`efivarfs`)**
– **Total Size:** 128 KB
– **Used:** 3.8 KB
– **Available:** 120 KB
– **Usage Percentage:** 4%

– **Boot Filesystems**
– **/boot (`/dev/nvme0n1p16`)**
– **Total Size:** 881 MB
– **Used:** 133 MB
– **Available:** 687 MB
– **Usage Percentage:** 17%

– **/boot/efi (`/dev/nvme0n1p15`)**
– **Total Size:** 105 MB
– **Used:** 6.1 MB
– **Available:** 99 MB
– **Usage Percentage:** 6%

### Analysis
– Your root filesystem is at 50% usage, which is reasonable, as you still have 3.4 GB available.
– Other temporary filesystems and the boot partitions have low usage percentages, indicating that they have plenty of available space.
– Overall, you have sufficient disk space remaining, and you should monitor usage regularly to ensure you don't approach capacity limits, especially on the root filesystem.

### Next Steps
– If you anticipate needing more space or if you plan to install additional software or store more data, consider increasing your EBS volume size or cleaning up unnecessary files to manage disk space effectively.
– You can also use commands like `du -sh /*` to identify directories using the most disk space if you need to clean up your instance further.

### 1. **Using SSH with Command Line Tools**

#### **Using `top`**
1. Connect to your EC2 instance using SSH:

ssh -i your-key.pem ubuntu@your-instance-public-dns

2. Run the `top` command:

top

– This command provides a real-time view of the CPU usage along with memory usage and running processes. Look for the CPU line, which shows the percentage of CPU in use.

#### **Using `htop`**
1. If you prefer a more user-friendly interface, you can install `htop`:

sudo apt update
   sudo apt install htop

2. After installation, run:

htop

– This provides a more colorful and interactive view of your CPU and memory usage. You can see individual CPU core usage and processes consuming the most CPU.

#### **Using `mpstat`**
If you want to see the CPU usage over time, you can use the `mpstat` command (part of the `sysstat` package). Install it if it's not already available:

sudo apt install sysstat

Then run:

mpstat -P ALL 1

– This will show CPU usage for all cores every second.

### 2. **Using AWS Management Console**

1. **Log in to your AWS Management Console.**
2. Navigate to the **EC2 Dashboard**.
3. Click on **Instances** and select your instance.
4. Go to the **Monitoring** tab.
– Here, you'll see the CPU utilization graph showing usage over time. You can adjust the time range to view different periods.

### 3. **Using AWS CLI**

If you prefer command-line tools, you can check CPU utilization using the AWS CLI:

1. Make sure the AWS CLI is installed and configured on your machine.
2. Use the following command to get the CPU usage metrics:

aws cloudwatch get-metric-statistics --metric-name CPUUtilization --start-time 2024-12-01T00:00:00Z --end-time 2024-12-01T23:59:59Z --period 300 --namespace AWS/EC2 --statistics Average --dimensions Name=InstanceId,Value=your-instance-id

– Replace `your-instance-id` with your actual EC2 instance ID. This command fetches the average CPU utilization over a specified time period.

### Summary
Using these methods, you can monitor the CPU usage of your EC2 instance in real-time or over specified periods. If you notice high CPU usage consistently, you may want to investigate running processes or consider upgrading your instance type for better performance.

### CPU Usage
– **Total Tasks:** 125
– **Running Tasks:** 1
– **Sleeping Tasks:** 124
– **Stopped Tasks:** 0
– **Zombie Tasks:** 0

– **CPU Utilization:**
– **User Space (`us`):** 0.2%
– **System Space (`sy`):** 0.2%
– **Nice (`ni`):** 0.0%
– **Idle (`id`):** 99.3%
– **I/O Wait (`wa`):** 0.2%
– **Hardware Interrupts (`hi`):** 0.0%
– **Software Interrupts (`si`):** 0.0%
– **Steal Time (`st`):** 0.2%

### Memory Usage
– **Total Memory:** 914.2 MiB
– **Free Memory:** 66.6 MiB
– **Used Memory:** 868.7 MiB
– **Buffer/Cache:** 140.3 MiB

– **Swap Memory:**
– **Total Swap:** 0.0 MiB
– **Free Swap:** 0.0 MiB
– **Used Swap:** 0.0 MiB
– **Available Memory (including buffers/cache):** 45.5 MiB

### Analysis
– **CPU Usage:** Your CPU is predominantly idle (99.3%), indicating that it is not under heavy load. The 1 running task is consuming minimal CPU resources.
– **Memory Usage:** You have 914.2 MiB of total memory, with 868.7 MiB used and only 66.6 MiB free. However, you have 140.3 MiB in buffers/cache, which the system can reclaim when needed, bringing your effective free memory to about 206.9 MiB (66.6 MiB free + 140.3 MiB buff/cache).
– **Swap Memory:** You are not using any swap memory, which is fine as long as you have enough RAM for your current workload. If you run out of RAM, the lack of swap space could lead to performance issues.

### Recommendations
– **Monitoring:** Keep an eye on memory usage, as you have a limited amount of RAM available. If your application starts to use more memory, you might need to optimize your processes or consider upgrading your instance type.
– **Swapping:** If you anticipate that you might need more memory in the future, consider creating a swap file. This can help prevent out-of-memory issues, especially if your application spikes in memory usage.

Overall, your instance seems to be performing well with low CPU usage, but monitor memory usage closely to ensure you do not encounter any performance bottlenecks.

### 1. **Monitor Memory Usage**
– Use tools like `htop`, `free -h`, or `vmstat` to monitor memory usage in real-time.
– Identify processes consuming excessive memory and investigate whether they can be optimized or replaced.

### 2. **Optimize Application Configuration**
– **Adjust Application Settings:** Configure your applications (web servers, databases, etc.) to use less memory. This can often be done through configuration files.
– For example, in PHP, adjust the `memory_limit` setting in `php.ini` to limit how much memory a script can use.
– In database configurations (like MySQL), optimize cache sizes and buffer settings.

– **Reduce Concurrent Connections:** Limit the number of concurrent connections your application can handle, if feasible. This can reduce memory pressure.

### 3. **Use Caching Wisely**
– Implement caching strategies to reduce memory consumption and improve performance.
– **In-Memory Caching:** Use tools like Redis or Memcached to cache frequently accessed data instead of recalculating or re-fetching it from a database.
– **Page Caching:** If you're running a web application, consider page caching to serve static content without using dynamic resources.

### 4. **Optimize Code and Dependencies**
– **Profile Your Code:** Use profiling tools (like Xdebug for PHP or profiling tools specific to your programming language) to identify memory leaks or inefficient memory usage in your code.
– **Remove Unused Packages:** Audit your application's dependencies and remove any unused libraries or packages to reduce memory overhead.

### 5. **Database Optimization**
– Optimize database queries to ensure they are efficient and do not consume excessive memory.
– Consider indexing frequently queried columns to speed up lookups and reduce memory usage.

### 6. **Use a Swap File (if necessary)**
– If your application occasionally exceeds available memory, consider adding a swap file to provide additional virtual memory. This can prevent out-of-memory errors, although it may slow down performance:

# Create a swap file
  sudo fallocate -l 1G /swapfile
  
  # Set the correct permissions
  sudo chmod 600 /swapfile
  
  # Set up the swap area
  sudo mkswap /swapfile
  
  # Enable the swap file
  sudo swapon /swapfile
  
  # To make it permanent, add it to /etc/fstab
  echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab

### 7. **Consider Instance Type**
– If your application consistently runs low on memory, consider upgrading your EC2 instance to a type with more RAM. Choose an instance type that aligns with your application's resource requirements.

### 8. **Implement Load Balancing**
– If your application supports it, implement a load balancer to distribute traffic across multiple instances. This can help ensure that no single instance becomes a bottleneck due to high memory usage.

### 9. **Containerization**
– If your application is not already containerized, consider using Docker or another container orchestration system (like Kubernetes). Containers can help isolate memory usage and improve resource management.

### 10. **Regular Maintenance**
– Regularly clean up logs, temporary files, and other data that may accumulate over time and consume memory.

### Summary
By actively monitoring and optimizing your application, adjusting configurations, and considering architectural changes, you can significantly reduce memory usage on your EC2 instance. These steps can enhance performance, prevent outages, and potentially reduce costs by allowing you to utilize smaller instance types effectively.