Feng
Zhou
This paper proposed a new approach called
LSTC, Log-Structured Transaction Cache, for the purpose of improving I/O
performance. Mostly for the “Database / Transaction” and “Office / Engineering”
environment, LSTC provides better performance as well as better reliability
than traditional file system buffer cache at very low extra costs. It also adds
to system availability and reduces maintaining time.
Based on the physical characteristics of
hard disks, we proposed LSTC. We point out that using on-disk log as the cache
for write operations, the system can exploit the high continual transfer rate
of modern disks and boosts writing performance of file system by magnitudes. We
also introduce the concept of IO transaction into LSTC, and explain that using
a log-structure transaction cache; we can solve the problem of maintaining
meta-data integrity, which has existed in Unix-like systems for a long
time. After summarizing the recent
development of hard disk, processor and DRAM, we conclude that most computers
today have the configuration for running LSTC to achieve better performance and
reliability. Simple trace-driven
simulations are carried out to evaluate the new architecture. Results show that
it improves performance considerably.
An implementation design under the Linux operating system is presented
in the form of architecture, algorithms, data structures and scenarios. Hierarchy, modularity and portability
are kept in mind when carrying out the design. Several problems, which we may encounter
in actual implementation, are also discussed.