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So, we can say that dedup has more disadvantages than advantages.=20
And what about dedup of Netapp?=20
Jose=20
----- Original Message -----
From: "Karli Sj=C3=B6berg" <Karli.Sjoberg(a)slu.se>=20
To: suporte(a)logicworks.pt=20
Cc: "Jiri Belka" <jbelka(a)redhat.com>, users(a)ovirt.org=20
Sent: Quinta-feira, 30 de Maio de 2013 8:33:19=20
Subject: Re: [Users] deduplication=20
ons 2013-05-29 klockan 09:59 +0100 skrev suporte@logicworks.pt:=20
Absolutely agree with you, planning is the best thing to do, but normally p=
eople want a plug'n'play system with all included, because there is not muc=
h time to think and planning, and there are many companies that know how to=
take advantage of this people characteristics.=20
Any way, I think another solution for dedup is FreeNAS using ZFS.=20
FreeNAS is just FreeBSD with a fancy web-ui ontop, so it=C2=B4s neither mor=
e or less of ZFS than you would have otherwise, And regarding dedup in ZFS;=
Just don=C2=B4t, it=C2=B4s not worth it! It=C2=B4s said that it may increa=
se performance when you have a very suitable usecase, e.g. everything exact=
ly the same over and over. What=C2=B4s not said is that scrubbing and resil=
vering slows down to a snail (from hundreds of MB/s, or GB if your system i=
s large enough, down to less than 10), just from dedup. Also deleting snaps=
hots of datasets that have(or have had) dedup on can kill the entire system=
, and when I say kill, I mean really fubar. Been there, regretted that... N=
ow, compression on the other hand, you get basically for free and gives dec=
ent savings, I highly recommend that.=20
/Karli=20
<blockquote
Jose=20
</blockquote
<blockquote
From: "Jiri Belka"
<jbelka(a)redhat.com>=20
To: suporte(a)logicworks.pt=20
Cc: users(a)ovirt.org=20
Sent: Quarta-feira, 29 de Maio de 2013 7:33:10=20
Subject: Re: [Users] deduplication=20
On Tue, 28 May 2013 14:29:05 +0100 (WEST)=20
suporte(a)logicworks.pt wrote:=20
That's why I'm making this questions, to demystify some
buzzwords around =
here.=20
But if you have a strong and good technology why not create buzzwords
to =
get into as many people as possible? without trapped them.=20
Share a disk containing "static" data is a good idea, do
you know from wh=
ere I can start?=20
Everything depends on your needs, design planning. Maybe then sharing=20
disk would be better to share via NFS/iscsi. Of course if you have many=20
VMs each of them is different you will fail. But if you have mostly=20
homogeneous environment you can think about this approach. Sure you have=20
to have plan for upgrading "base" "static" shared OS data, you have
to=20
have plan how to install additional software (different destination=20
than /usr or /usr/local)... If you already have your own build host=20
which builds for you OS packages and you have already your own plan for=20
deployment, you have done first steps. If you depend on upgrading each=20
machine separately from Internet, then first you should plan your=20
environment, configuration management etc.=20
Well, in many times people do not do any planning, they just think some=20
good technology would save their "poor" design.=20
j.=20
</blockquote
<blockquote
</blockquote
=09--=20
Med V=C3=A4nliga H=C3=A4lsningar=20
---------------------------------------------------------------------------=
----=20
Karli Sj=C3=B6berg=20
Swedish University of Agricultural Sciences=20
Box 7079 (Visiting Address Kron=C3=A5sv=C3=A4gen 8)=20
S-750 07 Uppsala, Sweden=20
Phone: +46-(0)18-67 15 66=20
karli.sjoberg(a)slu.se=20
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<html><head><style type=3D'text/css'>p { margin: 0;
}</style></head><body><=
div style=3D'font-family: arial,helvetica,sans-serif; font-size: 10pt; colo=
r: #000000'>So, we can say that dedup has more disadvantages than advantage=
s.<br><br>And what about dedup of
Netapp?<br><br>Jose<br><br><hr id=3D"zwch=
r"><div style=3D"color: rgb(0, 0, 0); font-weight: normal; font-style:
norm=
al; text-decoration: none; font-family: Helvetica,Arial,sans-serif; font-si=
ze: 12pt;"><b>From: </b>"Karli Sj=C3=B6berg"
&lt;Karli.Sjoberg(a)slu.se&gt;<b=
r><b>To: </b>suporte(a)logicworks.pt<br><b>Cc:
</b>"Jiri Belka" <jbelka@re=
dhat.com>, users(a)ovirt.org<br><b>Sent: </b>Quinta-feira, 30 de
Maio de 2=
013 8:33:19<br><b>Subject: </b>Re: [Users]
deduplication<br><br
ons 2013-05-29 klockan 09:59 +0100 skrev suporte(a)logicworks.pt:
<blockquote><font color=3D"#000000">Absolutely agree with you,
planning is =
the best thing to do, but normally people want a plug'n'play system with al=
l included, because there is not much time to think and planning, and there=
are many companies that
know how to take advantage of this people characteristics.</font><br
<font color=3D"#000000">Any way, I think
another solution for dedup is Free=
NAS using ZFS.</font><br
</blockquote
<br
FreeNAS is just FreeBSD with a fancy
web-ui ontop, so it=C2=B4s neither mor=
e or less of ZFS than you would have otherwise, And regarding dedup in ZFS;=
Just don=C2=B4t, it=C2=B4s not worth it! It=C2=B4s said that it
<b>may</b> increase performance when you have a very suitable usecase, e.g.=
everything
<b>exactly</b> the same over and over. What=C2=B4s not said is that scrubbi=
ng and resilvering slows down to a snail (from hundreds of MB/s, or GB if y=
our system is large enough, down to less than 10), just from dedup. Also de=
leting snapshots of datasets that have(or
have had) dedup on can kill the entire system, and when I say kill, I mean=
really fubar. Been there, regretted that... Now, compression on the other =
hand, you get basically for free and gives decent savings, I highly recomme=
nd that.<br
<br
/Karli<br
<br
<blockquote><br
<font
color=3D"#000000">Jose</font><br
<br
<br
<hr
align=3D"center"
</blockquote
<blockquote><b><font
color=3D"#000000">From: </font></b><font color=3D"#000=
000">"Jiri Belka"
&lt;jbelka(a)redhat.com&gt;</font><br
<b><font color=3D"#000000">To: </font></b><font
color=3D"#000000">suporte@l=
ogicworks.pt</font><br
<b><font
color=3D"#000000">Cc: </font></b><font
color=3D"#000000">users@ovi=
rt.org</font><br
<b><font
color=3D"#000000">Sent: </font></b><font
color=3D"#000000">Quarta-=
feira, 29 de Maio de 2013 7:33:10</font><br
<b><font color=3D"#000000">Subject:
</font></b><font color=3D"#000000">Re: =
[Users] deduplication</font><br
<br
<font
color=3D"#000000">On Tue, 28 May 2013 14:29:05 +0100
(WEST)</font><br=
<font color=3D"#000000">suporte(a)logicworks.pt
wrote:</font><br
<br
<font
color=3D"#000000">> That's why I'm making this questions, to
demys=
tify some buzzwords around here.
</font><br
<font
color=3D"#000000">> But if you have a strong and good technology w=
hy not create buzzwords to get into as many people as possible? without tra=
pped them.
</font><br
<font
color=3D"#000000">> Share a disk containing "static" data is
a goo=
d idea, do you know from where I can start?
</font><br
<br
<font
color=3D"#000000">Everything depends on your needs, design planning. =
Maybe then sharing</font><br
<font
color=3D"#000000">disk would be better to share via NFS/iscsi. Of cou=
rse if you have many</font><br
<font
color=3D"#000000">VMs each of them is different you will fail. But if=
you have mostly</font><br
<font
color=3D"#000000">homogeneous environment you can think about this ap=
proach. Sure you have</font><br
<font
color=3D"#000000">to have plan for upgrading "base"
"static" shared O=
S data, you have to</font><br
<font
color=3D"#000000">have plan how to install additional software (diffe=
rent destination</font><br
<font
color=3D"#000000">than /usr or /usr/local)... If you already have you=
r own build host</font><br
<font
color=3D"#000000">which builds for you OS packages and you have alrea=
dy your own plan for</font><br
<font
color=3D"#000000">deployment, you have done first steps. If you depen=
d on upgrading each</font><br
<font
color=3D"#000000">machine separately from Internet, then first you sh=
ould plan your</font><br
<font
color=3D"#000000">environment, configuration management
etc.</font><b=
r
<br
<font
color=3D"#000000">Well, in many times people do not do any planning, =
they just think some</font><br
<font
color=3D"#000000">good technology would save their "poor"
design.</fo=
nt><br
<br
<font
color=3D"#000000">j.</font><br
<br
</blockquote
<blockquote><br
<br
</blockquote
<br
<table
cellpadding=3D"0" cellspacing=3D"0" width=3D"100%"
<tbody
<tr
<td>-- <br
<br
Med V=C3=A4nliga
H=C3=A4lsningar<br
---------------------------------------------------------------------------=
----<br
Karli Sj=C3=B6berg<br
Swedish University of Agricultural Sciences<br
Box 7079 (Visiting Address Kron=C3=A5sv=C3=A4gen 8)<br
S-750 07 Uppsala, Sweden<br
Phone:
+46-(0)18-67 15 66<br
<a
href=3D"mailto:karli.sjoberg@adm.slu.se"
target=3D"_blank">karli.sjoberg=
@slu.se</a> </td
</tr
</tbody
</table
</div><br></div></body></html
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