我只是看着
MSDN documentation for ConcurrentDictionary,我在“示例”代码中看到了这一点：
// We know how many items we want to insert into the ConcurrentDictionary. // So set the initial capacity to some prime number above that,to ensure that // the ConcurrentDictionary does not need to be resized while initializing it. int NUMITEMS = 64; int initialCapacity = 101;
作为参考,MSDN示例中的字典如下初始化：@H_502_5@
ConcurrentDictionary<int,int> cd = new ConcurrentDictionary<int,int>(Environment.ProcessorCount * 2,initialCapacity); for (int i = 0; i < NUMITEMS; i++) cd[i] = i * i;
在该示例中,字典永远不会包含超过64个项目.为什么不将初始容量设置为64,而不是大于64的看似任意的素数？评论说,这是为了确保字典在初始化时不需要调整大小,但为什么要使用initialCapacity = 64的类似字典需要调整大小？为什么选择这个素数？@H_502_5@
