Apache Solr用Pattern替换“前缀”(Apache Solr Replacing “Prefixes” with Pattern)

 这似乎是iOS 5.x中的回归：它发生在5.0和5.1模拟器和5.1设备上，但不在4.3模拟器或4.3.2设备上。 
 
 它也特别是字符串绘图似乎被打破 - 如果您所做的只是字符串绘制（避免创建/销毁上下文的开销），崩溃几乎立即发生： 
 
-(void)threadFunc:(UIFont *)font {
  @autoreleasepool {
    NSString *string = @" ";
    CGRect r = {{0,0},{50,50}};
    UIGraphicsBeginImageContextWithOptions(r.size, YES, 0);
    for(;;) {
      @autoreleasepool {
        [string drawAtPoint:r.origin withFont:font];
      }
    }
    UIGraphicsEndImageContext();
  }
}

-(void)startThreads
{
  UIFont * font = [UIFont systemFontOfSize:12];
  for (int i = 2; i--;)
  {
    [NSThread detachNewThreadSelector:@selector(threadFunc:) toTarget:self withObject:font];
  }
}
 
 编辑：只在多核环境（即双核设备或模拟器，假设多核Mac）中“几乎是即时”。 否则，崩溃大约需要10-20分钟。 我没有双核iOS 4.x设备（唯一的可能性似乎是iPad 2），但单核设备在一个多小时后没有崩溃。 
 
 我已经向Apple提出了一个错误，如果它影响到你，我会鼓励你这样做。 

This appears to be a regression in iOS 5.x: It happens on the 5.0 and 5.1 simulators and on a 5.1 device, but not on the 4.3 simulator or a 4.3.2 device.
 
It's also specifically the string drawing that seems to be broken — if all you do is string-drawing (avoiding the overhead of creating/destroying contexts), the crash happens nearly instantly:
 
-(void)threadFunc:(UIFont *)font {
  @autoreleasepool {
    NSString *string = @" ";
    CGRect r = {{0,0},{50,50}};
    UIGraphicsBeginImageContextWithOptions(r.size, YES, 0);
    for(;;) {
      @autoreleasepool {
        [string drawAtPoint:r.origin withFont:font];
      }
    }
    UIGraphicsEndImageContext();
  }
}

-(void)startThreads
{
  UIFont * font = [UIFont systemFontOfSize:12];
  for (int i = 2; i--;)
  {
    [NSThread detachNewThreadSelector:@selector(threadFunc:) toTarget:self withObject:font];
  }
}
 
EDIT: It is "nearly instant" only in multi-core environments (i.e. a dual-core device or the simulator, assuming a multi-core Mac). Otherwise, it takes on the order of 10-20 minutes to crash. I don't have a dual-core iOS 4.x device (the only possibility appears to be the iPad 2), but the single-core devices haven't crashed after over an hour.
 
I've raised a bug with Apple, and encourage you to do the same if it affects you.