2.6.2/2.6.3 bdev floppy open/read/close 20x slower

[Bart Oldeman]

Hi,

the following program:

#include <unistd.h>
#include <fcntl.h>

int main(void)
{
	int i;
	for (i = 0; i < 10; i++) {
		char buf[512];
		int fd = open("/dev/fd0", O_RDWR);
		read(fd, buf, sizeof buf);
		close(fd);
	}
	return 0;
}

takes (here) 1 second for Linux kernel 2.6.1 but 20 seconds for 2.6.2/3.
Unless the floppy is mounted at the same time -- then it takes 2 seconds
first time for 2.6.2 and is cached subsequently.

I know there have been some changes to allow hotplugging but isn't this
side-effect a little too harsh?

Bart

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