Slack Space Recycling: Delaying On-Demand Cleaning in LFS for Performance and Endurance
نویسندگان
چکیده
The Log-structured File System (LFS) transforms random writes to a huge sequential one to provide superior write performance on storage devices. However, LFS inherently suffers from overhead incurred by cleaning segments. Specifically, when file system utilization is high and the system is busy, write performance of LFS degenerates significantly due to high cleaning cost. Also, in the newer flash memory based SSD storage devices, cleaning leads to reduced SSD lifetime as it incurs more writes. In this paper, we propose an enhancement to the original LFS to alleviate the performance degeneration due to cleaning when the system is busy. The new scheme, which we call Slack Space Recycling (SSR), allows LFS to delay on-demand cleaning during busy hours such that cleaning may be done when the load is much lighter. Specifically, it writes modified data directly to invalid areas (slack space) of used segments instead of cleaning on-demand, pushing back cleaning for later. SSR also has the added benefit of increasing the lifetime of the now popular SSD storage devices. We implement the new SSR-LFS file system in Linux and perform a large set of experiments. The results of these experiments show that the SSR scheme significantly improves performance of LFS for a wide range of storage utilization settings and that the lifetime of SSDs is extended considerably. key words: Log-structured File System, LFS cleaning, garbage collection, endurance, slack space recycling, solid state drive
منابع مشابه
HyLog: A High Performance Approach to Managing Disk Layout
Our objective is to improve disk I/O performance in multi-disk systems supporting multiple concurrent users, such as file servers, database servers, and email servers. In such systems, many disk reads are absorbed by large in-memory buffers, and so disk writes comprise a large portion of the disk I/O traffic. LFS (Log-structured File System) has the potential to achieve superior write performan...
متن کاملFile System Logging versus Clustering: A Performance Comparison
The Log-structured File System (LFS), introduced in 1991 [8], has received much attention for its potential order-of-magnitude improvement in file system performance. Early research results [9] showed that small file performance could scale with processor speed and that cleaning costs could be kept low, allowing LFS to write at an effective bandwidth of 62 to 83% of the maximum. Later work show...
متن کاملThe role of galanin receptors in anticonvulsant effect of low frequency stimulations on acquisition of perforant path kindled seizures in rats
Introduction: Low-frequency stimulation (LFS) has a delaying effect on kindled seizures acquisition. In the present study we examined the role of galanin receptors in the inhibitory effects of LFS on kindled seizures induced by electrical stimulation of perforant path. Methods: Animals were stimulated daily at the AD threshold intensity with a rapid kindling procedure. LFS was applied immed...
متن کاملA Novel Zone-Bit-Recording-Boosted Performance Scheme for Log-structured File System
I/O becomes a major performance bottleneck in modern computer systems because of the mechanic nature of disk drives. One important technique to improve disk performance is Zone-Bit-Recording (ZBR) technology, which increases the capacity by putting more data in the outer disk cylinders. A direct consequence of ZBR is that outer tracks have higher data transfer rates. LFS is another technique to...
متن کاملThe effect of the budget slack creation and budget internal control by managers on maximization of utility function in budgetary participation
When evaluating of the senior manager’s performance is based on the achieving to budget and they have responsibility to report the capacity of resources which are in their part too; it is possible to create budget slack and effect on their performance evaluation by providing pessimistic and conservatively estimates or manipulated information of income and expenses. So, Senior Manager and Budget...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- IEICE Transactions
دوره 96-D شماره
صفحات -
تاریخ انتشار 2013