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HTML5 textarea placeholder not appearing
...This is not true anymore, according to the HTML5 parsing spec:
If the next token is a U+000A LINE FEED (LF) character token,
then ignore that token and move on to the next one. (Newlines
at the start of textarea elements are ignored as an authoring
convenience.)
You might still have trouble if y...
PHP中9大缓存技术总结 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...hp的执行流程可以用下图来展示：
首先php代码被解析为Tokens，然后再编译为Opcode码，最后执行Opcode码，返回结果；所以，对于相同的php文件，第一次运行时可以缓存其Opcode码，下次再执行这个页面时，直接会去找到缓存下的opc...
Is it better practice to use String.format over string Concatenation in Java?
...er than doing just one instantiation most likely due to the overhead of re-allocating space for the looping append at the end of one builder).
String formatString = "Hi %s; Hi to you %s";
long start = System.currentTimeMillis();
for (int i = 0; i < 1000000; i++) {
String s =...
Adding values to a C# array
...might be concerned about performance.
The most efficient method is likely allocating a new array and then using Array.Copy or Array.CopyTo. This is not hard if you just want to add an item to the end of the list:
public static T[] Add<T>(this T[] target, T item)
{
if (target == null)
...
记一次MongoDB性能问题 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...验证这种可能，我搜索了一下MongoDB日志：
shell> grep FileAllocator /path/to/log
[FileAllocator] allocating new datafile ... filling with zeroes...
[FileAllocator] done allocating datafile ... took ... secs
我使用的文件系统是ext4（xfs也不错 ），创建数据文件...
What is copy-on-write?
...ncurrency sorts of problems. In ZFS, for example, data blocks on disk are allocated copy-on-write; as long as there are no changes, you keep the original blocks; a change changed only the affected blocks. This means the minimum number of new blocks are allocated.
These changes are also usually im...
How to add an Access-Control-Allow-Origin header
...ecloud.com/v1.0
From the results returned, extract the values for X-Auth-Token and X-Storage-Url
curl -X POST \
-H "Content-Type: font/woff" \
--header "X-Auth-Token: returned-x-auth-token" returned-x-storage-url/name-of-your-container/fonts/fontawesome-webfont.woff
curl -X POST \
-H "Cont...
How to use PHP OPCache?
...econds) to check file timestamps for changes to the shared
;memory storage allocation.
opcache.revalidate_freq=60
;If enabled, a fast shutdown sequence is used for the accelerated code
;The fast shutdown sequence doesn't free each allocated block, but lets
;the Zend Engine Memory Manager do the wor...
How to initialize static variables
...t of times the array could potentially be initialized - i.e., lots of heap allocation. Since php is written in C, I'd imagine the translation would resolve to a function returning a pointer to an Array per call... Just my two cents.
– zeboidlund
Aug 22 '12 at ...
Google OAuth 2 authorization - Error: redirect_uri_mismatch
... pass the code to your server, redeem it, and store the access and refresh tokens, then you have to use the literal string postmessage instead of the redirect_uri.
For example, building on the snippet in the Ruby doc:
client_secrets = Google::APIClient::ClientSecrets.load('client_secrets.json')
au...