caching

问题 Consider: In IE 9 , To clear Cache , I did: Open IE, Press F12, then Ctrl + R A pop-up "Are you sure you want to clear browser cache" pops up Select Yes. Filter: @WebFilter("*.*") public class NoCacheFilter implements Filter { @Override public void destroy() { } @Override public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException { HttpServletResponse response = (HttpServletResponse) res; response.setHeader("Cache-Control", "no-cache,

问题 A web app I'm working on requires frequent parsing of diverse web resources (HTML, XML, RSS, etc). Once downloaded, I need to cache these resources to minimize network load. The app requires a very straightforward cache policy: only re-download a cached resource when more than X minutes have passed since the access time. Should I: Store both the access time (e.g. 6/29/09 at 10:50 am) and the resource itself in the database. Store the access time and a unique identifier in the database. The

问题 I am trying to learn the usage of cache. From what I see by doing some sample experiment program, the time taken for execution of a program iterating through an array and doing some operations on the elements suddenly increases very much if I increase the array size beyond a particular value.Can anyone explain in simple terms how the cache size and array size affect the performance of mathematical operations on an array? 回答1: If the cache is not able to accumulate the array, any reference to

问题 I just followed a simple hibernate struts tutorial and succesfully made db calls through hibernate. However I don't see the code closing the hibernate connection anywhere. sessionFactory.getCurrentSession(); is used to get the session per request. Should I close this session when the user logs out? or after each request of is this something taken care of by the framework? a second related question is, In what kind of use case would I use a hibernate session interceptor? and a third question

问题 I am obtaining my cache object like this CacheAccess<Object, Object> cache = JCS.getInstance("queries"); I have put a config file in the classpath cache.ccf. For debugging reasons I want to set the aux disk cache path programmatically, but do not know how to obtain the interface I need. I know there exsists an attribute class where one may set this path, but I do not know how to get the instance of this class which refers to the cache I am using. Any ideas? 来源： https://stackoverflow.com

问题 This question already has answers here : Invalidate cache in Picasso (14 answers) Closed 3 months ago . if(isConnected()) { // if device online Picasso.with(context) .load(url) .networkPolicy(NetworkPolicy.NO_CACHE) .placeholder(R.drawable.ic_contact_picture) .error(R.drawable.ic_contact_picture) .into(imageView, new Callback() { @Override public void onSuccess() { } @Override public void onError() { Picasso.with(context).invalidate(url); } }); } else { // if device offline Picasso.with

问题 We're in the process of building an internal, Java-based RESTful web services application that exposes domain-specific data in XML format. We want to supplement the architecture and improve performance by leveraging a cache store. We expect to host the cache on separate but collocated servers, and since the web services are Java/Grails, a Java or HTTP API to the cache would be ideal. As requests come in, unique URI's and their responses would be cached using a simple key/value convention, for

问题 I have a News objects that extends ParseObject class. I'd like it to be cached locally so that I can fetch it from local store later. Here is my callback that includes call to .pinAllInBackground(..) method: FindCallback<News> onNewsReceived = new FindCallback<News>() { @Override public void done(List<News> arg0, ParseException arg1) { if (arg1 == null) { newsList = new ArrayList<News>(arg0); ParseObject.pinAllInBackground(newsList); initializeList(); } else { Log.d("TAG1", String.valueOf

问题 I have a Django project deployed with Gunicorn and nginx. I also have a memcached running and the Django cache middleware () set up to cache the site. Everything works fine when running with DEBUG=True, but when I switch to DEBUG=False I get the following error in Gunicorn log when trying to access the site: 2013-02-20 16:09:50 [25196] [ERROR] Error handling request Traceback (most recent call last): File "/home/toursprung/.virtualenvs/myproject/lib/python2.6/site-packages/gunicorn/workers

问题 If we consider an hierarchical single level write back cache with write allocate policy , then the formula for average access time during write operation is given by :- Twrite = (H)(Tc) + (1-H)(Tc + Tm + (x*Tm)). Where, H= hit ratio of cache. Tc=access time of cache. Tm= access time of memory. x= fraction of cache blocks which are dirty. The above formula is given in this site https://gateoverflow.in/14480/formula-write-back-write-through-access-time-parallel-serial?show=14502#a14502 However,