tailieunhanh - CAR: Clock with Adaptive Replacement

Clean all paint and primer from the areas to be welded. For those with a spot-welding attachment for their welding equipment, skip the next step. If not, drill 1/4” holes in the panel mounting points to correspond with the intended new spot welds. Refit the new panel to the car, double-checking its’ alignment with door edges, bonnet , headlamp surrounds and anywhere else it has to fit. Clamp it in place with vice-grips, small g-clamps or whatever fastening method you are using. In awkward corners a small self-tapping screw might be easier, as you must allow for constant checking of. | CAR Clock with Adaptive Replacement Sorav Bansaứ and Dharmendra S. Modhai Stanford University ÍIBM Almaden Research Center Emails sbansal@ dmodha@ Abstract CLOCK is a classical cache replacement policy dating back to 1968 that was proposed as a low-complexity approximation to LRU. On every cache hit the policy LRU needs to move the accessed item to the most recently used position at which point to ensure consistency and correctness it serializes cache hits behind a single global lock. CLOCK eliminates this lock contention and hence can support high concurrency and high throughput environments such as virtual memory for example Multics UNIX BSD AIX and databases for example DB2 . Unfortunately CLOCK is still plagued by disadvantages of LRU such as disregard for frequency susceptibility to scans and low performance. As our main contribution we propose a simple and elegant new algorithm namely CLOCK with Adaptive Replacement CAR that has several advantages over CLOCK i it is scan-resistant ii it is self-tuning and it adaptively and dynamically captures the recency and frequency features of a workload iii it uses essentially the same primitives as CLOCK and hence is low-complexity and amenable to a high-concurrency implementation and iv it outperforms CLOCK across a wide-range of cache sizes and workloads. The algorithm CAR is inspired by the Adaptive Replacement Cache ARC algorithm and inherits virtually all advantages of ARC including its high performance but does not serialize cache hits behind a single global lock. As our second contribution we introduce another novel algorithm namely CAR with Temporal filtering CART that has all the advantages of CAR but in addition uses a certain temporal filter to distill pages with long-term utility from those with only short-term utility. I. Introduction A. Caching and Demand Paging Modern computational infrastructure is rich in examples of memory hierarchies where a fast but expensive main cache memory .