Re: Re: about:conf->recovery_disabled and mddev->recovery_disabled

["majianpeng" <majianpeng@gmail.com>]

I readed the raid1:error(),I can't understand this code:
/*
	 * If it is not operational, then we have already marked it as dead
	 * else if it is the last working disks, ignore the error, let the
	 * next level up know.
	 * else mark the drive as failed
	 */
	if (test_bit(In_sync, &rdev->flags)
	    && (conf->raid_disks - mddev->degraded) == 1) {
		/*
		 * Don't fail the drive, act as though we were just a
		 * normal single drive.
		 * However don't try a recovery from this drive as
		 * it is very likely to fail.
		 */
		conf->recovery_disabled = mddev->recovery_disabled;
		return;
	}
question 1:
If error occur and the raid1 is recoveying,but the error did not occur because recovery operation.The recovery will continue.

question 2:
		when error occur,The disk may have to many error.so the code is :
		conf->recovery_disabled = mddev->recovery_disabled;
		But I can add a spare disk and recovery.
		Is it correctly?
																										Thanks!

------------------				 
majianpeng
2012-04-10

-------------------------------------------------------------
发件人：NeilBrown
发送日期：2012-04-09 08:03:38
收件人：majianpeng
抄送：linux-raid
主题：Re: about:conf->recovery_disabled and  mddev->recovery_disabled

On Sat, 7 Apr 2012 17:13:22 +0800 "majianpeng" <majianpeng@gmail.com> wrote:

> Hi all:
> 	I confused the recovery_disabled.
> 	what's the mean when conf->recovery_disabled = mddev->recovery_disabled?
> 	If equal,so not to add disk and not to recovery?

Yes, exactly.

in an attempt to recover a device fails we don't want to immediately retry as
that would cause a loop.
So whenever a recovery fails, we set conf->recovery_disabled to match
mddev->recovery_disable.  And whenever something changes which might make
recovery possible, we increment mddev->recovery_disabled, so that it tries
again.

With raid10, the 'recovery_disabled' is per-disk, not per-array.

NeilBrown