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Date:      Tue, 19 Nov 2013 10:25:03 -0800
From:      aurfalien <aurfalien@gmail.com>
To:        Eric Browning <ericbrowning@skaggscatholiccenter.org>
Cc:        FreeBSD FS <freebsd-fs@freebsd.org>
Subject:   Re: Performance difference between UFS and ZFS with NFS
Message-ID:  <5969250F-0987-4304-BB95-52C7BAE8D84D@gmail.com>
In-Reply-To: <CAM=5oeAF2gfccrGNdbApUDpqRae4OQjZ7oaZZi4y1j%2BsF6PsTw@mail.gmail.com>
References:  <2103733116.16923158.1384866769683.JavaMail.root@uoguelph.ca> <9F76D61C-EFEB-44B3-9717-D0795789832D@gmail.com> <CAM=5oeAF2gfccrGNdbApUDpqRae4OQjZ7oaZZi4y1j%2BsF6PsTw@mail.gmail.com>

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Curious.

Do you have NFS locking enabled client side?

Most likely you do as Mac Mail will not run w/o locks, nor will Adobe =
prefs like temp cache. etc...

So being this is prolly the case, could it be a mem pressure issue and =
not enough RAM?

So NFS locks take up RAM as does ARC.  What are your mem stats and swap =
stats during the 700% (yikes) experience?

- aurf

On Nov 19, 2013, at 10:19 AM, Eric Browning wrote:

> Aurf,
>=20
> I ran those two commands and it doesn't seem to have made a =
difference.  Usage is still above 700% and it still takes 30s to list a =
directory.  The time to list is proportional to the number of users =
logged in.  On UFS with all students logged in and hammering away at =
their files there is no noticeable speed decrease.
>=20
>=20
> On Tue, Nov 19, 2013 at 11:12 AM, aurfalien <aurfalien@gmail.com> =
wrote:
>=20
> On Nov 19, 2013, at 5:12 AM, Rick Macklem wrote:
>=20
> > Eric Browning wrote:
> >> Some background:
> >> -Two identical servers, dual AMD Athlon 6220's 16 cores total @ =
3Ghz,
> >> -64GB ram each server
> >> -Four Intel DC S3700 800GB SSDs for primary storage, each server.
> >> -FreeBSD 9 stable as of 902503
> >> -ZFS v28 and later updated to feature flags (v29?)
> >> -LSI 9200-8i controller
> >> -Intel I350T4 nic (only one port being used currently) using all =
four
> >> in
> >> LACP overtaxed the server's NFS queue from what we found out making
> >> the
> >> server basically unusable.
> >>
> >> There is definitely something going on between NFS and ZFS when =
used
> >> as a
> >> file server (random workload) for mac home directories.  They do =
not
> >> jive
> >> well at all and pretty much drag down these beefy servers and cause
> >> 20-30
> >> second delays when just attempting to list a directory on Mac 10.7,
> >> 10.8
> >> clients although throughput seems fast when copying files.
> >>
> >> This server's NFS was sitting north of 700% (7+ cores) all day long
> >> when
> >> using ZFSv28 raidz1. I have also tried stripe, compression on/off,
> >> sync
> >> enabled/disabled, and no dedup with 56GB of ram dedicated to ARC.
> >> I've
> >> tried just 100% stock settings in loader.conf and and some
> >> recommended
> >> tuning from various sources on the freebsd lists and other sites
> >> including
> >> the freebsd handbook.
> >>
> >> This is my mountpoint creation:
> >> zfs create -o mountpoint=3D/users -o sharenfs=3Don -o
> >> casesensitivity=3Dinsensitive -o aclmode=3Dpassthrough -o =
compression=3Dlz4
> >> -o
> >> atime=3Doff -o aclinherit=3Dpassthrough tank/users
> >>
> >> This last weekend I switched one of these servers over to a UFS =
raid
> >> 0
> >> setup and NFS now only eats about 36% of one core during the =
initial
> >> login
> >> phase of 150-ish users over about 10 minutes and sits under 1-3%
> >> during
> >> normal usage and directories all list instantly even when drilling
> >> down 10
> >> or so directories on the client's home files. The same NFS config =
on
> >> server
> >> and clients are still active.
> >>
> >> Right now I'm going to have to abandon ZFS until it works with NFS.
> >> I
> >> don't want to get into a finger pointing game, I'd just like to =
help
> >> get
> >> this fixed, I have one old i386 server I can try things out on if
> >> that
> >> helps and it's already on 9 stable and ZFS v28.
> >>
> > Btw, in previous discussions with Eric on this, he provided nfsstat
> > output that seemed to indicate most of his RPC load from the Macs
> > were Access and Getattr RPCs.
> >
> > I suspect the way ZFS handles VOP_ACCESSX() and VOP_GETATTR() is a
> > significant part of this issue. I know nothing about ZFS, but I =
believe
> > it does always have ACLs enabled and presumably needs to check the
> > ACL for each VOP_ACCESSX().
> >
> > Hopefully someone familiar with how ZFS handles VOP_ACCESSX() and
> > VOP_GETATTR() can look at these?
>=20
> Indeed.  However couldn't one simply disable ACL mode via;
>=20
> zfs set aclinherit=3Ddiscard pool/dataset
> zfs set aclmode=3Ddiscard pool/dataset
>=20
> Eric, mind setting these and see?
>=20
> Mid/late this week I'll be doing a rather large render farm test =
amongst our Mac fleet against ZFS.
>=20
> Will reply to this thread with outcome when I'm done.  Should be =
interesting.
>=20
> - aurf
>=20
> >
> > rick
> >
> >> Thanks,
> >> --
> >> Eric Browning
> >> Systems Administrator
> >> 801-984-7623
> >>
> >> Skaggs Catholic Center
> >> Juan Diego Catholic High School
> >> Saint John the Baptist Middle
> >> Saint John the Baptist Elementary
> >> _______________________________________________
> >> freebsd-fs@freebsd.org mailing list
> >> http://lists.freebsd.org/mailman/listinfo/freebsd-fs
> >> To unsubscribe, send any mail to =
"freebsd-fs-unsubscribe@freebsd.org"
> >>
> > _______________________________________________
> > freebsd-fs@freebsd.org mailing list
> > http://lists.freebsd.org/mailman/listinfo/freebsd-fs
> > To unsubscribe, send any mail to =
"freebsd-fs-unsubscribe@freebsd.org"
>=20
>=20
>=20
>=20
> --=20
> Eric Browning
> Systems Administrator
> 801-984-7623
>=20
> Skaggs Catholic Center
> Juan Diego Catholic High School
> Saint John the Baptist Middle
> Saint John the Baptist Elementary




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