Well there can be many metrics to compare the two Giant Hosting providers. Some of the important metrics to compare and decide the best option for you are as follows.
Comparison of Cost and Package
CPU Performance Benchmark
Memory Benchmarks
File I/O Benchmarks
MySQL Benchmarks
Apache Benchmarks
Network Benchmarks
RAM and Cache Size
These are the right metrics to compare both services and make a right selection for you.
But as for general, In my views I would vote for DigitalOcean. Because they have just lowered their prices and now they are giving 1GB server in just $5. Linode also offers 1GB server in the same price, But DigitalOcean servers have better cache which make their CPU more faster.
And you can get a Cheaper rate for DigitalOcean if you are looking a managed hosting service. You can check Cloudways, They are providing manage hosting servers and DO is cheaper then Linode in their plan For More information : https://www.cloudways.com/en/pricing.php