ccb-nas2021.pdf (404.2 kB)
Download fileConstant time garbage collection in SSDs
conference contribution
posted on 2022-01-11, 11:11 authored by Reza Salkhordeh, Kevin Kremer, Lars NagelLars Nagel, Dennis Maisenbacher, Hans Holmberg, Matias Bjorling, Andre BrinkmannThe Flash Translation Layer (FTL) plays a crucial role
for the performance and lifetime of SSDs. It has been
difficult to evaluate different FTL strategies in real SSDs
in the past, as the FTL has been deeply embedded into
the SSD hardware. Recent host-based FTL architectures
like ZNS now enable researchers to implement and
evaluate new FTL strategies. In this paper, we evaluate
the overhead of various garbage collection strategies
using a host-side FTL, and show their performance
limitations when scaling the SSD size or the number
of outstanding requests. To address these limitations,
we propose constant cost-benefit policy, which removes
the scalability limitations of previous policies and can
be efficiently deployed on host-based architectures. The
experimental results show that our proposed policy
significantly reduces the CPU overhead while having
a comparable write amplification compared to the best
previous policies.
History
School
- Science
Department
- Computer Science