Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 10 Nov 2015 12:56:54 +0100
From:      Marko Turk <markoml@markoturk.info>
To:        "Eugene M. Zheganin" <emz@norma.perm.ru>
Cc:        FreeBSD <freebsd-stable@freebsd.org>
Subject:   Re: zfs, mc, mcview and files opening
Message-ID:  <20151110115654.GA1949@vps.markoturk.info>
In-Reply-To: <5641BFC8.9050207@norma.perm.ru>
References:  <5641BFC8.9050207@norma.perm.ru>

next in thread | previous in thread | raw e-mail | index | archive | help

--h31gzZEtNLTqOjlF
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

Hi,

On Tue, Nov 10, 2015 at 02:58:32PM +0500, Eugene M. Zheganin wrote:
> Hi.
>=20
> my midnight commander is terribly slow at vieweing files with mcview.
> Opening of a file of approximately 10 megabytes takes about 30-40
> seconds. This isn't related with the compression setting, %busy wait or
> pool properties- I tested on various machines, it's fully reproducible.
> This lag appears on files about 1.5 megs in size, and the lag time is
> pretty constant.  From my observation, it's the following syscall that's
> blocking:
>=20
> fstat(4,{ mode=3Dp--------- ,inode=3D41,size=3D0,blksize=3D4096 }) =3D 0 =
(0x0)
> (observed using `truss mcview maillog`)
>=20
> If the file is viewed not by mcview (i.e. it is of a special type and
> viewed by the special utility, or mcview is simply not used - for
> example more opens same file without lag) - the file is opening fast as
> always. When mcview is involved - lag appears. In the same time I've
> never seen this lag on filesystems other than zfs.

Is this happening on every ZFS FreeBSD install or just some of them? I'm
running ZFS on FreeBSD 10-STABLE and I don't see this problem (even for
much larger files).

BR,
Marko

> And the most
> beautiful detail is that this lag is repeatable on multiple opens of
> same file - though you can expect that it will be only first time that
> would be that slow, it doesn't happen - same pause occurs on sequential
> opens.
>=20
> Who's issue is this ?
> Can some workaround be used ?
>=20
> Thanks.
> Eugene.

--h31gzZEtNLTqOjlF
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2
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=EFE+
-----END PGP SIGNATURE-----

--h31gzZEtNLTqOjlF--



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20151110115654.GA1949>