> On Mon, 29 Jun 2009, NightBird wrote:
> >
> > I checked the output of iostat. svc_t is between 5
> and 50, depending on when data is flushed to the disk
> (CIFS write pattern). %b is between 10 and 50.
> > %w is always 0.
> > Example:
> > device r/s w/s kr/s kw/s wait actv svc_t
> %w %b
> sd27 31.5 127.0 935.9 616.7 0.0 11.9 75.2
> 0 66
> d28 5.0 0.0 320.0 0.0 0.0 0.1 18.0
> 0 9
> > This tells me disks are busy but I do not know what
> they are doing?
> > are they spending time seeking, writting or
> reading?
>
> It looks like your sd27 is being pounded with write
> iops. It is close
> to its limit.
>
> Can you post complete iostat output? Since you have
> so many disks,
> (which may not always be involved in the same stripe)
> you may need to
> have iostat average over a long period of time such
> as 30 or 60
> seconds in order to see a less responsive disk.
> Disks could be less
> esponsive for many reasons, including vibrations in
> their operating
> environment.
>
> Also see Jeff Bonwick's "diskqual.sh" as described at
>
> http://www.mail-archive.com/zfs-disc...@opensolaris.or
> g/msg15384.html
> which is good at helping to find pokey disks. A
> slightly modified
> version is included below.
>
> Bob
> --
> Bob Friesenhahn
> bfrie...@simple.dallas.tx.us,
> http://www.simplesystems.org/users/bfriesen/
> GraphicsMagick Maintainer,
> http://www.GraphicsMagick.org/
I will run the script when the server is idle as recommended and report back.
Here is the full iostat output (30sec). c9t40d0 seems to have a consistently
higher svc_t time.
r/s w/s kr/s kw/s wait actv wsvc_t asvc_t %w %b device
0.0 2.6 2.1 11.0 0.0 0.0 0.0 6.5 0 1 c8t0d0
0.1 2.6 0.4 11.0 0.0 0.0 0.0 5.1 0 0 c8t1d0
6.0 6.2 380.1 147.8 0.0 0.3 0.0 23.6 0 13 c9t8d0
6.2 6.5 390.8 147.9 0.0 0.3 0.0 21.9 0 13 c9t9d0
6.3 6.2 386.1 147.6 0.0 0.3 0.0 26.7 0 12 c9t10d0
6.7 6.2 413.5 147.8 0.0 0.3 0.0 21.9 0 14 c9t11d0
6.1 5.7 371.1 147.6 0.0 0.3 0.0 21.2 0 11 c9t12d0
6.7 5.9 407.3 147.6 0.0 0.3 0.0 21.4 0 13 c9t13d0
5.7 6.3 347.6 147.7 0.0 0.3 0.0 22.4 0 12 c9t14d0
7.0 5.9 426.5 147.5 0.0 0.3 0.0 20.6 0 13 c9t15d0
6.6 6.1 405.0 147.6 0.0 0.3 0.0 21.1 0 12 c9t16d0
6.6 6.2 405.2 147.7 0.0 0.3 0.0 21.1 0 12 c9t17d0
7.1 6.3 432.9 147.8 0.0 0.3 0.0 20.9 0 14 c9t18d0
6.7 6.5 411.6 147.9 0.0 0.3 0.0 23.6 0 13 c9t19d0
6.4 6.4 390.3 148.1 0.0 0.3 0.0 21.7 0 13 c9t20d0
6.9 6.9 424.4 147.9 0.0 0.3 0.0 19.8 0 13 c9t21d0
6.2 6.9 375.3 148.1 0.0 0.3 0.0 20.2 0 12 c9t22d0
5.7 6.8 349.5 147.9 0.0 0.3 0.0 20.9 0 12 c9t23d0
6.2 6.6 377.5 147.9 0.0 0.3 0.0 20.6 0 11 c9t24d0
5.4 6.7 328.2 147.9 0.0 0.2 0.0 20.7 0 11 c9t25d0
6.7 6.7 407.3 148.0 0.0 0.3 0.0 19.8 0 12 c9t26d0
6.5 6.9 396.7 148.1 0.0 0.3 0.0 20.4 0 13 c9t27d0
6.4 6.6 390.4 147.9 0.0 0.3 0.0 21.3 0 13 c9t28d0
6.8 6.3 416.0 147.6 0.0 0.4 0.0 26.8 0 13 c9t29d0
6.8 6.3 413.9 147.8 0.0 0.3 0.0 23.5 0 13 c9t30d0
7.5 33.5 446.9 312.0 0.0 1.8 0.0 45.0 0 18 c9t31d0
8.2 33.6 491.7 312.0 0.0 2.1 0.0 51.1 0 21 c9t32d0
7.0 34.3 414.9 312.3 0.0 1.9 0.0 47.0 0 20 c9t33d0
7.6 34.1 463.4 312.2 0.0 2.1 0.0 51.2 0 21 c9t34d0
7.9 33.5 474.4 312.0 0.0 2.2 0.0 52.9 0 21 c9t35d0
8.2 33.2 496.0 311.7 0.0 2.4 0.0 59.1 0 23 c9t36d0
8.0 33.2 481.0 311.9 0.0 2.0 0.0 48.8 0 21 c9t37d0
7.8 33.4 469.9 311.9 0.0 2.3 0.0 56.4 0 20 c9t38d0
8.5 34.1 518.7 312.4 0.0 2.3 0.0 54.3 0 22 c9t39d0
8.4 32.9 510.5 311.8 0.0 2.9 0.0 70.6 0 27 c9t40d0
8.2 34.3 501.5 312.4 0.0 2.3 0.0 55.1 0 24 c9t41d0
8.1 34.3 491.1 312.5 0.0 2.3 0.0 55.4 0 21 c9t42d0
8.5 34.3 510.9 312.7 0.0 2.3 0.0 53.3 0 23 c9t43d0
7.5 34.3 453.1 312.6 0.0 2.3 0.0 54.4 0 20 c9t44d0
7.0 33.7 420.9 312.1 0.0 2.3 0.0 55.7 0 19 c9t45d0
7.0 34.2 420.9 312.4 0.0 2.3 0.0 55.2 0 20 c9t46d0
7.9 35.1 474.6 312.5 0.0 2.1 0.0 49.1 0 22 c9t47d0
8.1 35.0 487.4 312.8 0.0 2.3 0.0 52.8 0 22 c9t48d0
8.1 34.2 491.3 312.2 0.0 2.1 0.0 50.2 0 20 c9t49d0
7.2 34.6 429.4 312.5 0.0 2.1 0.0 51.3 0 20 c9t50d0
7.6 35.2 459.3 312.6 0.0 2.3 0.0 54.1 0 21 c9t51d0
7.7 35.0 463.5 312.6 0.0 2.1 0.0 49.2 0 21 c9t52d0
7.4 35.1 442.6 312.8 0.0 2.1 0.0 48.8 0 21 c9t53d0
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