From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shaohua Li Subject: Re: [PATCH] md: limit mdstat resync progress to max_sectors Date: Fri, 1 Dec 2017 11:40:46 -0800 Message-ID: <20171201194046.dzjy35lnjugqidlm@kernel.org> References: <20171130163330.26309-1-nate.dailey@stratus.com> <1ef7fb87-65a9-1008-5c5d-43012f078a16@suse.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Nate Dailey Cc: Guoqing Jiang , linux-raid@vger.kernel.org List-Id: linux-raid.ids On Fri, Dec 01, 2017 at 08:36:07AM -0500, Nate Dailey wrote: > Yes, I also wondered if setting curr_resync to MaxSector could be changed... > but not understanding why it's done, it seemed safer to just catch this in > status_resync. we use it to set rdev->recovery_offset, but that doesn't mean we must set it to MaxSector though. I applied the patch as-is, it's not a big issue. Thanks, Shaohua > > Nate > > > > On 12/01/2017 03:37 AM, Guoqing Jiang wrote: > > Actually, it is recovery :). > > > > > > On 12/01/2017 12:33 AM, Nate Dailey wrote: > > > There is a small window near the end of md_do_sync where mddev->curr_resync > > > can be equal to MaxSector. > > > > I am curious about the purpose of set it to MaxSector, maybe the setting > > is not > > necessary. > > > > Acked-by: Guoqing Jiang > > > > Thanks, > > Guoqing > > > > > If status_resync is called during this window, the resulting /proc/mdstat > > > output contains a HUGE number of = signs due to the very large curr_resync: > > > > > > Personalities : [raid1] > > > md123 : active raid1 sdd3[2] sdb3[0] > > > 204736 blocks super 1.0 [2/1] [U_] > > > [===================================================================== > > > ... (82 MB more) ... > > > ================>] recovery =429496729.3% (9223372036854775807/204736) > > > finish=0.2min speed=12796K/sec > > > bitmap: 0/1 pages [0KB], 65536KB chunk > > > > > > Modify status_resync to ensure the resync variable doesn't exceed > > > the array's max_sectors. > > > > > > Signed-off-by: Nate Dailey > > > --- > > > drivers/md/md.c | 4 +++- > > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > > > diff --git a/drivers/md/md.c b/drivers/md/md.c > > > index 41c050b59ec4..4e4dee0ec2de 100644 > > > --- a/drivers/md/md.c > > > +++ b/drivers/md/md.c > > > @@ -7605,7 +7605,9 @@ static int status_resync(struct seq_file *seq, > > struct mddev *mddev) > > > if (test_bit(MD_RECOVERY_DONE, &mddev->recovery)) > > > /* Still cleaning up */ > > > resync = max_sectors; > > > - } else > > > + } else if (resync > max_sectors) > > > + resync = max_sectors; > > > + else > > > resync -= atomic_read(&mddev->recovery_active); > > > > > > if (resync == 0) { > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html