关于MMC/CD usb storage 设备大量传输出现内核崩溃的解决办法

最近调试sd卡问题 ，出现一个问题：在卡内处理大量数据时（如运行cp或者tar）出现内核崩溃，搜很多网站都不行。最后考虑是不是虚拟内存不足造成的 。清一下内存 果然凑效。运行如下：

while true ; do echo 3 > /proc/sys/vm/drop_caches ; sleep 1 ; done & 

   有关解释可以参考下面

　有关/proc/sys/vm/drop_caches的用法如下:

　　Writing to this will cause the kernel to drop clean caches, dentries and inodes from memory, causing that memory to become free.

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6 ##To free pagecache:
echo 1 > /proc/sys/vm/drop_caches
##To free dentries and inodes:
echo 2 > /proc/sys/vm/drop_caches
##To free pagecache, dentries and inodes:
echo 3 > /proc/sys/vm/drop_caches

　　As this is a non-destructive operation and dirty objects are not freeable, the user should run `sync’ first.