caching

问题 In Java, are there equivalences to functions such as GNU C extensions prefetch and align(64) , that is, cache line alignment? 回答1: Not that I know of because it doesn't make sense in a compile-on-demand system. With Java, it's the run-time optimizer's job to figure this stuff out and the best result is going to depend on the current platform which may or may not benefit from the constructs that prefetch and align offer. 来源： https://stackoverflow.com/questions/10056407/java-and-cache-memory

问题 Environment: PHP: version 7.3 OS: Ubuntu 18.04 References followed: PHP - apc_store PHP - apc_fetch I cannot use apc_fetch from separate PHP script "file2" to access stored cache. It does work when trigger apc_fetch from file1. File: 1_store_variable_in_memory.php <?php $token = "my_token_value"; apc_store('token_1', $token); // var_dump(apc_fetch('token_1')); // Moved to file 2 File: 2_access_memory_stored_variable.php <?php var_dump(apc_fetch('token_1')); Result from file 2: bool(false)

问题 Please tell me about System.Web.Caching.Cache.NoSlidingExpiration in ASP.NET. 回答1: There's information here from MSDN - NoSlidingExpiration Specifies that an item expires at a set time, regardless of how often it is accessed. For example, you can set an item to expire at 6:00 PM or after four hours. If there was something else you wanted to ask about, please edit your question so we can help further. 来源： https://stackoverflow.com/questions/1819144/system-web-caching-cache-noslidingexpiration

问题 is there a noticeable speed performance difference when you cache the data which you retrieve from the database to a file on the filesystem (eg.: htdocs/cache/cachefile) rather than grabbing it directy from the MySQL DB? Thanks a lot! 回答1: This highly depends on your disk IO, the size of your database, the database configuration, the link to your database, the optimization of the database, etc, etc. So there is no definitive answer to that. You might want to consider memcached for your

问题 I'm building an app using AngularJS. I need to store some data across sessions. I thought the $cacheFactory might be an option. However, I can't figure out where the Cache object actually stores the data. Can someone tell me how to store data on the client-side across sessions in AngularJS? Is the $cacheFactory even an option for this scenario? Thank you 回答1: $cacheFactory merely stores the data in a JSON dict (called caches at the time of writing) and the data will be lost as soon as the app

问题 I'm building an app using AngularJS. I need to store some data across sessions. I thought the $cacheFactory might be an option. However, I can't figure out where the Cache object actually stores the data. Can someone tell me how to store data on the client-side across sessions in AngularJS? Is the $cacheFactory even an option for this scenario? Thank you 回答1: $cacheFactory merely stores the data in a JSON dict (called caches at the time of writing) and the data will be lost as soon as the app

问题 I want to use apc_store() to cache some results. But I need to know where the data will be stored, and what's the limit. Does it always store on memory? Or also writes to disk? I would prefer that the data that is not accessed very frequently is stored on disk. Should I use a different caching system for that? Is this the limit? apc.shm_size = 32MB . If so, what happens when I exceed it? 回答1: Data stored in the APC variable cache via apc_store() is always stored in memory. If you need to

问题 Suppose I have a C++11 application where two threads write to different but nearby memory locations, using simple pointers to primitive types. Can I be sure that both these writes will end up in memory eventually (probably after both have reached a boost::barrier), or is there a risk that both CPU cores hold their own cache line containing that data, and the second core flushing its modification to RAM will overwrite and undo the modification done by the first write? I hope that cache

问题 I'm new to Laravel. I've done research on the topic, but I can't seem to find an answer that clears things up for me. I know Laravel's default cache driver is set to file , which I can change. It also has some artisan cache commands, such as: php artisan config:cache php artisan route:cache 1) Even if Laravel has some built-in commands and features that automatically handle some cache (didn't understand exactly what parts), I still have to manually use the Cache facade on query results, right

问题 I have a an asp.net-mvc site. On one of the pages, I have an image, I use jcrop to allow users to crop the image. When this click submit, I crop the image on the server side and then reload the page. The issue is that the image looks the same as before . . if i hit F5 and refresh the page then the updated image shows up.. Is there anyway to avoid having to force a F5 refresh in this case? 回答1: This is a trick, but it works. Put a variable and random number in the image url. Something like: