caching

问题 In Agner Fog's "Optimizing subroutines in assembly language - section 11.8 Cache control instructions," he says: "Memory writes are more expensive than reads when cache misses occur in a write-back cache. A whole cache line has to be read from memory, modified, and written back in case of a cache miss. This can be avoided by using the non-temporal write instructions MOVNTI, MOVNTQ, MOVNTDQ, MOVNTPD, MOVNTPS . These instructions should be used when writing to a memory location that is unlikely

问题 I am building a "proxy client" extension for chrome and i have following scenario: Users can login to the extension and get a token from API. Tokens are valid for 2 hours. After login users can select a proxy server from a list and that proxy is set with chrome.proxy api. I am using Squid on proxy servers. When a user connects to a proxy server and lands on onAuthRequired i return email and token as authCredentials. Chrome uses those credentials from cache until token is not valid anymore and

问题 I have a class called cache. It is an generic, abstract class responsible for handling the global cache for forever type extends the class. My question is, if I have a static variable under the base class, will the static variable be unique per extending type or will it be the same for all types that extend Cache. For example the interface: Cache<K, V> private static Cache<K, V> [creates a cache store on first load] static V get(K key); Then I have an implementing class: PersonCache extends

问题 I am trying to use different cache system on my environments. I would like to have, for example, Filesystem for dev and memcached for prod . I am using symfony 3.3.10 . To achieve this, I would like to autowire the CacheInterface as follow: use Psr\SimpleCache\CacheInterface; class Api { public function __construct(CacheInterface $cache) { $this->cache = $cache; } } Here are my configuration files: config_dev.yml : framework: cache: app: cache.adapter.filesystem config_prod.yml : framework:

问题 Larger caches are usually with longer bitlines or wordlines and thus most likely higher access latency and cycle time. So, does L2 caches work in the same domain as L1 caches? How about L3 cache (slices) since they are now non-inclusive and shared among all the cores? And related questions are: Are all function units in a core in the same clock domain? Are the uncore part all in the same clock domain? Are cores in the multi-core system synchronous? I believe clock domain crossing would

问题 Someone know how to force a page cache in the browser? I need to reload a page several times, and the browser isn't caching the page! 回答1: If browser is not caching the page there's no much you can do than using one of them: <meta http-equiv="Cache-control" content="public"> OR <meta http-equiv="Cache-control" content="private"> You can't programatically override browser settings. It would be a security issue! 回答2: Even if you have <meta http-equiv="Cache-control" content="public"> there are

问题 I need to clear cache on certain condition from PHP code. How can I do so. I know that there is object Cache exists in opencart engine, but how do delete cache correctly. Or it is possible to delete just folders ? Please give advice. 回答1: In OpenCart there are 3 places that store cache image cache is located at public_html/image/cache if you have vQmod public_html/vqmod/vqcache system (data) cache public_html/system/cache You can delete files within these folders - do not delete the cache

问题 I've seen many articles about caching data for client in angular universal apps, so it doesn't duplicate the requests on client that has been already resolved on server. I just don't get how the data is transferred from server to the client. Do I inject the JSON to pre-rendered HTML or am I missing something else ? 回答1: As of angular 5, there is a module inside angular core called TransferStateModule that does this for you. https://angular.io/api/platform-browser/TransferState You simply add

问题 I've seen many articles about caching data for client in angular universal apps, so it doesn't duplicate the requests on client that has been already resolved on server. I just don't get how the data is transferred from server to the client. Do I inject the JSON to pre-rendered HTML or am I missing something else ? 回答1: As of angular 5, there is a module inside angular core called TransferStateModule that does this for you. https://angular.io/api/platform-browser/TransferState You simply add

问题 My system uses a bunch of micro service to process an item and I am planning to create a Stateful MicroService which holds the latest state of the item. In that service, I am planning to store all the item state in a reliable dictionary and whenever an item is accessed update the Last accessed field of the item. My requirement is that, I only want to store the recently used items in the reliable collection and need to move the items that are not accessed for long time to an external storage