Skip site navigation (1)Skip section navigation (2)
Date:      Fri, 11 Nov 2022 23:02:19 +0300
From:      Mehmet Erol Sanliturk <m.e.sanliturk@gmail.com>
To:        andy thomas <andy@time-domain.co.uk>
Cc:        freebsd-fs@freebsd.org
Subject:   Re: Odd behaviour of two identical ZFS servers mirroring via rsync
Message-ID:  <CAOgwaMuoLQ9Er67Y%2B=q%2Bf9724v2WT3L5v5TZaRVXq%2B=1vEyJ%2BA@mail.gmail.com>
In-Reply-To: <alpine.BSF.2.22.395.2211111709230.29479@mail0.time-domain.net>
References:  <alpine.BSF.2.22.395.2211111709230.29479@mail0.time-domain.net>

next in thread | previous in thread | raw e-mail | index | archive | help
--00000000000026b43905ed376002
Content-Type: text/plain; charset="UTF-8"

, Nov 11, 2022 at 8:42 PM andy thomas <andy@time-domain.co.uk> wrote:

> I have two identical servers, called clustor2 and clustor-backup, each
> with a ZFS RAIDZ-1 pool containing 9 SAS hard disks plus one spare and two
> SSDs for the ZIL and ARC functions. clustor2 stores user data from a
> HPC while clustor2-backup uses rsync to mirrors all the data from clustor2
> every 24 hours.
>
> However, the disk usage on the mirror server is considerably more than on
> the other server - attached is a screenshot showing the two servers side
> by side, with the mirror server on the right, and displaying the contents
> of the same subdirectory choen at random (named 'ratio_10.0' in this
> instance); as you can see, the sizes of the files within each of the
> folders are identical but 'du' reports very different
> space usages for each folder and 'zpool list' also reports a significant
> difference in ZFS pool size.
>
> I'm not sure if this is relevant but both servers have ZFS pools with no
> compression although lz4 compression is enabled on the ZFS filesystems &
> both run FreeBSD 11.3 with ZFS version 5.
>
> Perhaps using zfs send/receive instead of rsync for mirroring might solve
> this disparity?
>
> Thanks in advance for any suggestions,
>
> Andy




Your question I am understanding the following points .



I am using  rsync  in Fedora Linux .

There are  parameters of  rsync  such as

 --delete

to delete files from the destination drive when they do not exist in the
source drive .


Please carefully scan  rsync  parameters and use suitable ones for your
application .


If  a parameter like  --delete  is not used , rsync  copies new files from
the source drive and
it does not delete any files from the destination drive .


With my best wishes for all .


Mehmet Erol Sanliturk

--00000000000026b43905ed376002
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

<div dir=3D"ltr"><div dir=3D"ltr"><div class=3D"gmail_default" style=3D"fon=
t-family:tahoma,sans-serif;font-size:large"><br></div></div><div dir=3D"ltr=
"><div class=3D"gmail_quote"><div dir=3D"ltr" class=3D"gmail_attr">, Nov 11=
, 2022 at 8:42 PM andy thomas &lt;<a href=3D"mailto:andy@time-domain.co.uk"=
 target=3D"_blank">andy@time-domain.co.uk</a>&gt; wrote:<br></div><blockquo=
te class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px =
solid rgb(204,204,204);padding-left:1ex">I have two identical servers, call=
ed clustor2 and clustor-backup, each <br>
with a ZFS RAIDZ-1 pool containing 9 SAS hard disks plus one spare and two =
<br>
SSDs for the ZIL and ARC functions. clustor2 stores user data from a <br>
HPC while clustor2-backup uses rsync to mirrors all the data from clustor2 =
<br>
every 24 hours.<br>
<br>
However, the disk usage on the mirror server is considerably more than on <=
br>
the other server - attached is a screenshot showing the two servers side <b=
r>
by side, with the mirror server on the right, and displaying the contents <=
br>
of the same subdirectory choen at random (named &#39;ratio_10.0&#39; in thi=
s <br>
instance); as you can see, the sizes of the files within each of the <br>
folders are identical but &#39;du&#39; reports very different <br>
space usages for each folder and &#39;zpool list&#39; also reports a signif=
icant <br>
difference in ZFS pool size.<br>
<br>
I&#39;m not sure if this is relevant but both servers have ZFS pools with n=
o <br>
compression although lz4 compression is enabled on the ZFS filesystems &amp=
; <br>
both run FreeBSD 11.3 with ZFS version 5.<br>
<br>
Perhaps using zfs send/receive instead of rsync for mirroring might solve <=
br>
this disparity?<br>
<br>
Thanks in advance for any suggestions,<br>
<br>
Andy</blockquote><div><br></div><div><br></div><div><br></div><div><div sty=
le=3D"font-family:tahoma,sans-serif;font-size:large" class=3D"gmail_default=
">Your question I am understanding the following points .</div><br></div><d=
iv><br></div><div><br></div><div><div style=3D"font-family:tahoma,sans-seri=
f;font-size:large" class=3D"gmail_default">I am using=C2=A0 rsync=C2=A0 in =
Fedora Linux .</div><div style=3D"font-family:tahoma,sans-serif;font-size:l=
arge" class=3D"gmail_default"><br></div><div style=3D"font-family:tahoma,sa=
ns-serif;font-size:large" class=3D"gmail_default">There are=C2=A0 parameter=
s of=C2=A0 rsync=C2=A0 such as <br></div><div style=3D"font-family:tahoma,s=
ans-serif;font-size:large" class=3D"gmail_default"></div><div style=3D"font=
-family:tahoma,sans-serif;font-size:large" class=3D"gmail_default"><br></di=
v><div style=3D"font-family:tahoma,sans-serif;font-size:large" class=3D"gma=
il_default">=C2=A0--delete <br></div><div style=3D"font-family:tahoma,sans-=
serif;font-size:large" class=3D"gmail_default"><br></div><div style=3D"font=
-family:tahoma,sans-serif;font-size:large" class=3D"gmail_default">to delet=
e files from the destination drive when they do not exist in the source dri=
ve .</div><div style=3D"font-family:tahoma,sans-serif;font-size:large" clas=
s=3D"gmail_default"><br></div><div style=3D"font-family:tahoma,sans-serif;f=
ont-size:large" class=3D"gmail_default"><br></div><div style=3D"font-family=
:tahoma,sans-serif;font-size:large" class=3D"gmail_default">Please carefull=
y scan=C2=A0 rsync=C2=A0 parameters and use suitable ones for your applicat=
ion .</div><div style=3D"font-family:tahoma,sans-serif;font-size:large" cla=
ss=3D"gmail_default"><br></div><div style=3D"font-family:tahoma,sans-serif;=
font-size:large" class=3D"gmail_default"><br></div><div style=3D"font-famil=
y:tahoma,sans-serif;font-size:large" class=3D"gmail_default">If=C2=A0 a par=
ameter like=C2=A0 --delete=C2=A0 is not used , rsync=C2=A0 copies new files=
 from the source drive and</div><div style=3D"font-family:tahoma,sans-serif=
;font-size:large" class=3D"gmail_default">it does not delete any files from=
 the destination drive .</div><div style=3D"font-family:tahoma,sans-serif;f=
ont-size:large" class=3D"gmail_default"><br></div><div style=3D"font-family=
:tahoma,sans-serif;font-size:large" class=3D"gmail_default"><br></div><div =
style=3D"font-family:tahoma,sans-serif;font-size:large" class=3D"gmail_defa=
ult">With my best wishes for all .</div><div style=3D"font-family:tahoma,sa=
ns-serif;font-size:large" class=3D"gmail_default"><br></div><div style=3D"f=
ont-family:tahoma,sans-serif;font-size:large" class=3D"gmail_default"><br><=
/div><div style=3D"font-family:tahoma,sans-serif;font-size:large" class=3D"=
gmail_default">Mehmet Erol Sanliturk<br></div><div style=3D"font-family:tah=
oma,sans-serif;font-size:large" class=3D"gmail_default"><br></div><div styl=
e=3D"font-family:tahoma,sans-serif;font-size:large" class=3D"gmail_default"=
><br></div><div style=3D"font-family:tahoma,sans-serif;font-size:large" cla=
ss=3D"gmail_default"><br></div><div style=3D"font-family:tahoma,sans-serif;=
font-size:large" class=3D"gmail_default"><br></div><div style=3D"font-famil=
y:tahoma,sans-serif;font-size:large" class=3D"gmail_default"><br></div><div=
 style=3D"font-family:tahoma,sans-serif;font-size:large" class=3D"gmail_def=
ault"></div><br></div><div>=C2=A0</div></div></div>
</div>

--00000000000026b43905ed376002--



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAOgwaMuoLQ9Er67Y%2B=q%2Bf9724v2WT3L5v5TZaRVXq%2B=1vEyJ%2BA>