lru

I often do interactive work in Python that involves some expensive operations that I don't want to repeat often. I'm generally running whatever Python file I'm working on frequently. If I write: import functools32 @functools32.lru_cache() def square(x): print "Squaring", x return x*x I get this behavior: >>> square(10) Squaring 10 100 >>> square(10) 100 >>> runfile(...) >>> square(10) Squaring 10 100 That is, rerunning the file clears the cache. This works: try: safe_square except NameError: @functools32.lru_cache() def safe_square(x): print "Squaring", x return x*x but when the function is

The error looks like this Exception in thread "Thread-1" java.lang.NullPointerException at java.util.LinkedHashMap$Entry.remove(LinkedHashMap.java:332) at java.util.LinkedHashMap$Entry.recordAccess(LinkedHashMap.java:356) at java.util.LinkedHashMap.get(LinkedHashMap.java:304) at Server.getLastFinishedCommands(Server.java:9086) at Server.processPacket(Server.java:484) at PacketWorker.run(PacketWorker.java:34) at java.lang.Thread.run(Thread.java:744) Inside getLastFinishedCommands I use public List<CCommand> getLastFinishedCommands(UserProfile player) { List<CCommand> returnList = new ArrayList

一、什么是Cache 1 概念 Cache ，即 高速缓存 ，是介于CPU和内存之间的高速小容量存储器。在金字塔式存储体系中它位于自顶向下的第二层，仅次于CPU寄存器。其容量远小于内存，但速度却可以接近CPU的频率。 当CPU发出内存访问请求时，会先查看 Cache 内是否有请求数据。 如果存在（命中），则直接返回该数据； 如果不存在（失效），再去访问内存 —— 先把内存中的相应数据载入缓存，再将其返回处理器。 提供“高速缓存”的 目的 是让数据访问的速度适应CPU的处理速度，通过减少访问内存的次数来提高数据存取的速度。 2 原理 Cache 技术所依赖的原理是”程序执行与数据访问的 局部性原理 “，这种局部性表现在两个方面： 时间局部性 ：如果程序中的某条指令一旦执行，不久以后该指令可能再次执行，如果某数据被访问过，不久以后该数据可能再次被访问。 空间局部性 ：一旦程序访问了某个存储单元，在不久之后，其附近的存储单元也将被访问，即程序在一段时间内所访问的地址，可能集中在一定的范围之内，这是因为指令或数据通常是顺序存放的。 时间局部性是通过将近来使用的指令和数据保存到Cache中实现。空间局部性通常是使用较大的高速缓存，并将 预取机制 集成到高速缓存控制逻辑中来实现。 3 替换策略 Cache的容量是有限的，当Cache的空间都被占满后，如果再次发生缓存失效

I am working on implementing a MRU(Most Recently Used) cache in my project using C#. I googled some conceptions and implementations about MRU, and its contrary, LRU(Least Recently Used), and found this article http://www.informit.com/guides/content.aspx?g=dotnet&seqNum=626 that describes the implementation of MRU collection in C#. To confuse me is that I think this implementation is LRU rather than MRU. Could anyone help me to confirm this collection class is MRU or not? Following code block is the whole MRUCollection class. Thanks. class MruDictionary<TKey, TValue> { private LinkedList

I have seen the following code, and I think that there is a useless while loop in the implementation of addElement method. It should never happen to have more elements than size+1 since there is already a write lock. So why is the addElement method removing elements till it gets this condition true while(concurrentLinkedQueue.size() >=maxSize) Any pointers around this would be great. Here is the Implementation: public class LRUCache<K,V> { private ConcurrentLinkedQueue<K> concurrentLinkedQueue = new ConcurrentLinkedQueue<K>(); private ConcurrentHashMap<K,V> concurrentHashMap = new

I want to limit the size of the BlockingCollection. If I want to add another item and the collection is full, the oldest must be removed. Is there some Class specific to this task or my solution is ok? BlockingCollection<string> collection = new BlockingCollection<string>(10); string newString = ""; //Not an elegant solution? if (collection.Count == collection.BoundedCapacity) { string dummy; collection.TryTake(out dummy); } collection.Add(newString); EDIT1: Similar question here: ThreadSafe FIFO List with Automatic Size Limit Management What you are describing is a LRU cache. There is no

I have used Memory LRU Caching for caching bitmaps in my android application.but after some of the bitmaps are loaded into LRU map app force closes saying out of memory exception. I have spent whole day behind this but yet not found the solution please anyone can help me out I am badly stuck in this problem.Thanks in advance. HERE IS MY CODE final int maxMemory = (int) (Runtime.getRuntime().maxMemory()/1024); final int cacheSize = maxMemory / 8; bitmapHashMap = new LruCache<String, Bitmap>(cacheSize) { @SuppressLint("NewApi") @Override protected int sizeOf(String key, Bitmap value) { if