Firehose

A Linux eBPF (Extended Berkeley Packet Filter) security agent can achieve a 90% reduction in CPU cost by implementing a memoization-based cache to store the results of path-based policy checks, allowing for faster enforcement of access control rules. The cache uses a key-value pair approach, storing the inode number, mount namespace ID, and mount ID, and utilizing bitmasks to store policies for space efficiency. This approach enables the agent to avoid repetitive path walks and reduces kernel CPU cycles. AI summary