caching

问题 I would like to cache the result of the twitter api result and display them to users.. What's the best method to cache the result? I'm thinking a writing the result into a file based on a time limit.. Is that ok or any other method should be used? And most importantly what would be the ideal cache time ? I would like to display the latest content from the twitter but the twitter api has the request limits.. And my site has solid visitors/day.. 回答1: The cleanest way to do this would be to use

问题 Lets say you have a fragment of the page which displays the most recent posts, and you expire it in 30 minutes. I'm using Rails here. <% cache("recent_posts", :expires_in => 30.minutes) do %> ... <% end %> Obviously you don't need to do the database lookup to get the most recent posts if the fragment exists, so you should be able to avoid that overhead too. What I'm doing now is something like this in the controller which seems to work: unless Rails.cache.exist? "views/recent_posts" @posts =

问题 The DB load on my site is getting really high so it is time for me to cache common queries that are being called 1000s of times an hour where the results are not changing. So for instance on my city model I do the following: def self.fetch(id) Rails.cache.fetch("city_#{id}") { City.find(id) } end def after_save Rails.cache.delete("city_#{self.id}") end def after_destroy Rails.cache.delete("city_#{self.id}") end So now when I can City.find(1) the first time I hit the DB but the next 1000 times

问题 I have some places where implementing some sort of cache might be useful. For example in cases of doing resource lookups based on custom strings, finding names of properties using reflection, or to have only one PropertyChangedEventArgs per property name. A simple example of the last one: public static class Cache { private static Dictionary<string, PropertyChangedEventArgs> cache; static Cache() { cache = new Dictionary<string, PropertyChangedEventArgs>(); } public static

问题 I want to load a webpage, and if it was already loaded before and not modified then load it from cache. If it is found to be modified, then clear this page in the cache and reload. How can I do this? Write the webpage into the cache Find the webpage in the cache Show the webpage from the cache Clear the cache and load a new version if the page was modified Please help me. It would be awesome if can show me the code for each of the above. Best regards. 回答1: If you are ok with using Webview

问题 UPDATES : Even if i don't retrieve images from cache, i tried to retrieve via Drawable where i stored all the 18 images in the "drawable-mdpi" folder. Still, a blank screen was display. I was able to retrieved images from the server and save the image (.GIF) into the cache. However, when i need to load that image from cache, the image doesn't show up on screen. Here is the codes that does the work: File cacheDir = context.getCacheDir(); File cacheMap = new File(cacheDir, smallMapImageNames

问题 On my website, www.johnshammas.com, it works perfectly in all browsers. Except...anyone that has viewed the previous version on Chrome is stuck with that version until they empty their cache. What would cause the website to return a "not modified" header when in reality it has been modified heavily? 回答1: If a 304 Not Modified response was returned, it was because earlier the server sent a response with an ETag or a Last-Modified header. Later, the browser sent this value as an ETag or If

问题 Project X has the following parts: a. Spring Data repository with separate methods like: @Cacheable(value = "xobjects", unless = "#result == null") XObject findByParamA(String paramA); @Cacheable(value = "xobjects", unless = "#result == null") XObject findByParamB(String paramB); @CacheEvict("xobjects") <E extends XObject> E save(E entity); b. Hibernate that also uses "xobjects" cache. Problem #1 Since there are 2 ways of adding object to cache it could be the situation when the same object

问题 For instance, if you exit your Yahoo mail and then click the back button, it will not load the last page, it will redirect you to the login page. I have to do this with my PHP code, I'm using CodeIgniter. Some friends told me to disable caching but that will be a bad thing because I have a lot of images in my system and it would be bad to download them every time. How do I do this with PHP? 回答1: Disable caching of your page with the following code : http://php.net/manual/en/function.header

问题 Consider the diagrammed data cache architecture. (ASCII art follows.) -------------------------------------- | CPU core A | CPU core B | | |------------|------------| Devices | | Cache A1 | Cache B1 | with DMA | |-------------------------| | | Cache 2 | | |------------------------------------| | RAM | -------------------------------------- Suppose that an object is shadowed on a dirty line of Cache A1, an older version of the same object is shadowed on a clean line of Cache 2, and the newest