Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 29 Feb 2020 11:49:48 -0300
From:      Mario Olofo <mario.olofo@gmail.com>
To:        bsd-lists@bsdforge.com
Cc:        FreeBSD Stable <freebsd-stable@freebsd.org>
Subject:   Re: Running FreeBSD on M.2 SSD
Message-ID:  <CAP4Gn9DqqwSQEGcF_2t%2BP-FyKM5NfXGfn5n2aJYBUY=W__76Gg@mail.gmail.com>
In-Reply-To: <10e3153ee81dcd7919079cd0bfc16656@udns.ultimatedns.net>
References:  <CAP4Gn9CPtsrSTia%2BsSyT7yRiSHGfO0qJGPGrqR7sOSth7dsiwg@mail.gmail.com> <10e3153ee81dcd7919079cd0bfc16656@udns.ultimatedns.net>

next in thread | previous in thread | raw e-mail | index | archive | help
Hello, sorry my lack of vocabulary and thanks for the clarification
I think that it's a waste of space for me, and I'm afraid that this empty
space is making the problem just less frequent.
I remember that many years ago I implemented a FFS for an embedded system,
and the SD Card was 4k "aligned", with the smallest block being 512 bytes.
The only difference really is when I write/read from it, I have to align
the command to request x blocks starting at some 4k aligned address, even
if I just want 1 block.
As the system had a lot of small files, I did the FFS on top of this as 1k
sectors, I hoped that the ZFS could do something like that (ie. read/write
every 4k but with 1k sectors).

Mario

Em s=C3=A1b., 29 de fev. de 2020 =C3=A0s 01:54, Chris <bsd-lists@bsdforge.c=
om>
escreveu:

> On Fri, 28 Feb 2020 21:44:45 -0300 Mario Olofo mario.olofo@gmail.com said
>
> > Hello guys, a little update that let me more confused
> >
> > I reinstalled the FreeBSD with 4k pages using the sysctl
> > vfs.zfs.min_auto_ashift =3D 12 and no errors after a lot of stress I pu=
t on
> > it.
> > One thing that I noticed is that with the pool as 4k, the disk fill up
> very
> > fast, recompiling the kernel used my 8GB space and didn't even complete=
d.
> > But now I don't know if the 4k is the correct answer or if this just
> delays
> > the problem as the pages are bigger.
> The TLDR of 4k vs 512 largely has to do with the size of the files going
> onto your medium. Many files of a smaller size fit better on a 512
> boundary.
> Whereas larger mp3s or archives fair better on a 4k boundary. BTW these a=
re
> called SECTOR sizes. Not pages. :) 4k blocks typically read faster, than
> the
> 512 blocks (sectors). Because more data can be consumed in one read/write=
.
> So really, your going to have to decide how best to "tune" your disk to
> best
> suite it's intended use. Many small files. Or big files, and storage.
>
> HTH
>
> --Chris
> FreeBSD 14.0-FUTURE #0.000 cray256
> >
> > Mario
> >
> > Em sex., 28 de fev. de 2020 =C3=A0s 13:18, Mario Olofo <mario.olofo@gma=
il.com
> >
> > escreveu:
> >
> > > Yes, tried 4k quirk but not on install because don't know how to, I
> did a
> > > clean install then patch and rebuild the kernel, but
> > > the volume was already configured for 512bytes, I think I would need =
to
> > > create manually the volume, but don't remember how to anymore xD
> > > But I'll search some tutorials and try. From what I saw, the patch
> > > suggested on bugzilla got merged into the stable branch, so the quirk
> will
> > > be
> > > detected to use 4k in the installer in a near future.
> > >
> > > Mario
> > >
> > > Em sex., 28 de fev. de 2020 =C3=A0s 12:52, Theron <theron.tarigo@gmai=
l.com>
> > > escreveu:
> > >
> > >> On 2020-02-28 09:14, Mario Olofo wrote:
> > >> > Thanks!
> > >> >
> > >> > The only thing that I didn't checked was the questions of Theron,
> about
> > >> > misaligned data.
> > >> > The layout of the disk is as follows:
> > >> >
> > >> > Disco /dev/sdb: 447,1 GiB, 480113590272 bytes, 937721856 setores
> > >> > Unidades: setor de 1 * 512 =3D 512 bytes
> > >> > Tamanho de setor (l=C3=B3gico/f=C3=ADsico): 512 bytes / 512 bytes
> > >> > Tamanho E/S (m=C3=ADnimo/=C3=B3timo): 512 bytes / 512 bytes
> > >> > Tipo de r=C3=B3tulo do disco: gpt
> > >> > Identificador do disco: D1725E60-D734-4461-90F8-E9EB2376A65A
> > >> >
> > >> > Dispositivo    In=C3=ADcio       Fim   Setores Tamanho Tipo
> > >> > /dev/sdb1        2048   1023999   1021952    499M Windows ambiente
> de
> > >> > recupera=C3=A7=C3=A3o
> > >> > /dev/sdb2     1024000   1228799    204800    100M Sistema EFI
> > >> > /dev/sdb3     1228800   1261567     32768     16M Microsoft
> reservado
> > >> > /dev/sdb4     1261568 532482047 531220480  253,3G Microsoft dados
> b=C3=A1sico
> > >> > /dev/sdb5   532482048 549257215  16775168      8G FreeBSD ZFS
> > >> > /dev/sdb6   549257216 937719807 388462592  185,2G Linux sistema de
> > >> arquivos
> > >> >
> > >> > The zfsroot was configured automatically by the installer, so I
> think
> > >> that
> > >> > it align the volume automaticaly right?
> > >> >
> > >> > Mario
> > >>
> > >> Yes, I don't see any potential alignment issue here.  I would wonder
> if
> > >> this drive is misrepresenting its physical sector size, deceiving ZF=
S
> > >> and the SATA driver into making small writes that the drive does not
> > >> actually support, but it looks like you may have already tried the
> > >> relevant workaround:
> > >>
> > >> On 2020-02-27 23:44, Mario Olofo wrote:
> > >> > Maybe the problem really is a combination of factors, for the pers=
on
> > >> that
> > >> > filed a bug on bugzilla the fix was setting the quirks 4k and
> > >> broken_trim,
> > >> > but for me the real block size is 512bytes and only setting the fl=
ag
> > >> > broken_trim didn't help...
> > >> >
> > >> > Mario
> > >> Did you try 4k quirk ?
> > >>
> > >> Theron
> > >>
> > >
> > _______________________________________________
> > freebsd-stable@freebsd.org mailing list
> > https://lists.freebsd.org/mailman/listinfo/freebsd-stable
> > To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.or=
g
> "
>
>
> _______________________________________________
> freebsd-stable@freebsd.org mailing list
> https://lists.freebsd.org/mailman/listinfo/freebsd-stable
> To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.org"
>



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAP4Gn9DqqwSQEGcF_2t%2BP-FyKM5NfXGfn5n2aJYBUY=W__76Gg>