Proving Kangaroo Works Efficiently

Results

Let’s look at the results of Kangaroo’s design and optimization in practice.

Consider we have the following graph where we have miss ratio and days on the y-axis and x-axis, respectively. We are comparing miss ratio for all three systems; log-structured, set-associative cache, and Kangaroo’s; over a 7-day Facebook trace. All systems are running with 16 GB DRAM, a 1.9 TB drive, and with write rates less than 62.5 MB/s.

The worst performance out of these three options is the log-structured cache and this is because it’s severely constrained under our setup. Even with being generous in terms of DRAM to log-structured cache, it cannot index the whole flash capacity and thus the ...