I/O System Calls

The project is centered around performance. Try to get disk I/O as fast as possible and evaluate the effects of caches and the cost of system calls.

When running a Ubuntu container in Docker, you should make the container run in privileged mode by adding the --privileged parameter, which will give the container higher privileges, including permission to modify the filesystem.

Part 1 - Basics

Execute the following commands:

# Compile the C source code to an executable file
gcc run.c -o run
# Test run.c
./run <filename> [-r|-w] <block_size> <block_count>

The total file size, elapsed time, and performance of read/write operations will be output on success.

Part 2 - Measurement

Execute the following commands:

# Create an 8 GiB file for testing
./run test2.txt -w 8192 1048576
# Compile the C source code to an executable file
gcc run2.c -o run2
# Test run2.c
./run2 test2.txt 4096

The reasonable file size for the reasonable reading time will be output on success.

If you want to test run2.c with another file or different block count, you can prepare the test file and run:

./run2 <filename> <block_size>

Extra credit - dd

Ensure that the machine is already in a sudo mode or run by a root user.

Execute the following commands:

# Run dd program
sudo dd if=test2.txt of=/dev/null bs=4096 count=1048576

You can change the file name if, block size bs, and block count count in the dd command.

Extra credit - Google Benchmark

Ensure the Google Benchmark is installed globally.

Execute the following commands:

# Compile the C++ source code to an executable file
g++ run2_benchmark.cc -o run2_benchmark -lbenchmark -pthread
# Test run2_benchmark.cc
./run2_benchmark

If you want to change the test cases and its corresponding arguments for Google Benchmark, you should directly change it in run2_benchmark.cc.

Part 3 - Raw Performance

Ensure that the machine is already in a sudo mode or run by a root user.

Execute the following commands:

# Create a 4 GiB file for testing
./run test3.txt -w 4096 1048576
# Set the executable permission for the script
chmod +x ./run3.sh
# Run the script
./run3.sh test3.txt

This script contains cache-clearing commands. The total file size, elapsed time, and performance of read operations will be output on success.

If you want to run run3.sh with another file, you can prepare the test file and run:

./run3.sh <filename>

Part 4 - Caching

Ensure that the machine is already in a sudo mode or run by a root user.

Execute the following commands:

# Create a 4 GiB file for testing
./run test4.txt -w 4096 1048576
# Set the executable permission for the script
chmod +x ./run4.sh
# Run the script
./run4.sh test4.txt

This script contains cache-clearing commands. The total file size, elapsed time, and performance of no-cache and cache read operations will be output respectively on success.

If you want to run run4.sh with another file, you can prepare the test file and run:

./run4.sh <filename>

Part 5 - System Calls

Ensure that the machine is already in a sudo mode or run by a root user.

Execute the following commands:

# Create a 4 GiB file for testing
./run test5.txt -w 4096 1048576
# Set the executable permission for the script
chmod +x ./run5.sh
# Run the script
./run5.sh test5.txt

This script contains cache-clearing commands. Upon success, it will output the total size of the file executed when each system call (read, lseek, mmap) is called, the time spent, and the performance, respectively.

If you want to run run5.sh with another file, you can prepare the test file and run:

./run5.sh <filename>

Part 6 - Raw Performance

Execute the following commands:

# Compile the C source code to an executable file
gcc fast.c -o fast
# Test fast.c
./fast ubuntu-21.04-desktop-amd64.iso

If you want to run fast.c with another file, you can prepare the test file and run:

./fast <file_to_read>

If you want to reproduce the performance in our graphs in this part, you have to prepare the ubuntu-21.04-desktop-amd64.iso file to be tested and run the following commands (optional):

# Set the executable permission for the script
chmod +x ./fast_read_fread_pread.sh
# Run the script
./fast_read_fread_pread.sh
# Set the executable permission for the script
chmod +x ./fast_pread_mmap.sh
# Run the script
./fast_pread_mmap.sh

If you try to produce the graphs with a different file, you have to change the scripts directly.

Extra credit - AWS Cloud

Assume that the running environment on AWS Cloud has been prepared completely.

Execute the following commands:

# Set the executable permission for the script
chmod +x ./fast_aws.sh
# Run the script
./fast_aws.sh ubuntu-21.04-desktop-amd64.iso

If you want to run ./fast_aws.sh with another file, you can prepare the test file and run:

./fast_aws.sh <file_to_read>