Re: [gentoo-user] Re: ZFS formating
On Fri, Nov 1, 2013 at 11:29 AM, James wrote: > livedvd-x86-amd64-32ul-20121221.iso > Is what you are referring to? > yes > > I suggested using SystemRescue, because I had to clean up > (hack extensively) on Grub2 before the system would boot standalone. > In that first Pentoo install, I use ext2 for /boot and ext4 for / > > I don't use grub. I have an ext2 /boot and lilo on a md stripe :) > > If I use ZFS, /boot / and swap are all ZFS partitions, right? > they can be, but don't have to be. i've seen several people put swap onto a zram device -- Douglas J Hunley (doug.hun...@gmail.com) Twitter: @hunleyd Web: douglasjhunley.com G+: http://google.com/+DouglasHunley
[gentoo-user] Re: ZFS formating
Douglas J Hunley gmail.com> writes: > the latest gentoo live image has full zfs support on it -- Douglas J Hunley (doug.hunley gmail.com) livedvd-x86-amd64-32ul-20121221.iso Is what you are referring to? I suggested using SystemRescue, because I had to clean up (hack extensively) on Grub2 before the system would boot standalone. In that first Pentoo install, I use ext2 for /boot and ext4 for / If I use ZFS, /boot / and swap are all ZFS partitions, right? That's probably the last thing I'm working on is the Exact, simple disk/partion/ZFS setup to experiment around with the Pentoo workstation Besides, I'm not the swiftest on this list at juggling the intersection of GPT, UEFI, Grub2 and the newer file systems. Not to mention mtab, fstab, systemD etc etc... So you will not insult me, offering up snippent, syntax and a copy of a working (ZFS) fstab and grub file details James
Re: [gentoo-user] Re: ZFS
On Thu, Sep 19, 2013 at 8:01 PM, Grant wrote: You should definitely determine the right value for ashift on pool creation (it controls the alignment on the medium). It's an option that you afaik can only set on filesystem creation and therefore needs a restart from scratch if you get it wrong. According to the illumos wiki it's possible to run a mixed pool (if you have drives requiring different alignments[1]) If in doubt: ask ryao (iirc given the right information he can tell you which are the right options for you if you can't deduce it yourself). Choosing the wrong alignment can cause severe performance loss (that's not a ZFS issue but happened when 4k sector drives appeared and tools like fdisk weren't aware of this). >>> >>> Yikes... >>> >>> Ok, shouldn't there be a tool or tools to help with this? Ie, boot up on a >>> bootable tools disk on the system with all drives connected, then let it >>> 'analyze' your system, maybe ask you some questions (ie, how you will be >>> configuring the drives/RAID, etc), then spit out an optimized config for >>> you? >>> >>> It is starting to sound like you need to be a dang engineer just to use >>> ZFS... >>> >> >> Just do ashift=12 and you're good to go. No need to analyze further. >> >> The reason I said that because in the future, *all* drives will have 4 >> KiB sectors. Currently, many drives still have 512 B sectors. But when >> one day your drive dies and you need to replace it, will you be able >> to find a drive with 512 B sectors? >> >> Unlikely. >> >> That's why, even if your drives are currently of the 'classic' 512 B >> ones, go with ashift=12 anyway. >> >> For SSDs, the situation is murkier. Many SSDs 'lie' about their actual >> sector size, reporting to the OS that their sector size is 512 B (or 4 >> KiB). No tool can pierce this veil of smokescreen. The only way is to >> do research on the Internet. > > OK, so figure out what SSD you're using and Google to find the correct ashift? > > - Grant > Kind of like that, yes. Find out exactly the size of the SSD's "internal sectors" (for lack of better term), and find the log2 to it. But don't go higher than ashift=14 Rgds, -- FdS Pandu E Poluan ~ IT Optimizer ~ • LOPSA Member #15248 • Blog : http://pepoluan.tumblr.com • Linked-In : http://id.linkedin.com/in/pepoluan
Re: [gentoo-user] Re: ZFS
>> Especially with SSDs. One must find out the blocksize used by his/her SSDs. >> >> With spinning disks, setting ashift=12 is enough since no spinning >> disks have sectors larger than 2^12 bytes. >> >> With SSDs, one might have to set ashift=13 or even ashift=14. > > May I suggest that we should somehow collect all these small but > important issues for reference? Wiki? This could be useful: http://www.funtoo.org/wiki/ZFS_Install_Guide - Grant
Re: [gentoo-user] Re: ZFS
>>> You should definitely determine the right value for ashift on pool >>> creation >>> (it controls the alignment on the medium). It's an option that you afaik >>> can only set >>> on filesystem creation and therefore needs a restart from scratch if you >>> get it >>> wrong. >>> According to the illumos wiki it's possible to run a mixed pool (if you >>> have >>> drives requiring different alignments[1]) >>> If in doubt: ask ryao (iirc given the right information he can tell you >>> which >>> are the right options for you if you can't deduce it yourself). >>> Choosing the wrong alignment can cause severe performance loss (that's not >>> a ZFS issue but happened when 4k sector drives appeared and tools like >>> fdisk >>> weren't aware of this). >> >> Yikes... >> >> Ok, shouldn't there be a tool or tools to help with this? Ie, boot up on a >> bootable tools disk on the system with all drives connected, then let it >> 'analyze' your system, maybe ask you some questions (ie, how you will be >> configuring the drives/RAID, etc), then spit out an optimized config for >> you? >> >> It is starting to sound like you need to be a dang engineer just to use >> ZFS... >> > > Just do ashift=12 and you're good to go. No need to analyze further. > > The reason I said that because in the future, *all* drives will have 4 > KiB sectors. Currently, many drives still have 512 B sectors. But when > one day your drive dies and you need to replace it, will you be able > to find a drive with 512 B sectors? > > Unlikely. > > That's why, even if your drives are currently of the 'classic' 512 B > ones, go with ashift=12 anyway. > > For SSDs, the situation is murkier. Many SSDs 'lie' about their actual > sector size, reporting to the OS that their sector size is 512 B (or 4 > KiB). No tool can pierce this veil of smokescreen. The only way is to > do research on the Internet. OK, so figure out what SSD you're using and Google to find the correct ashift? - Grant
Re: [gentoo-user] Re: ZFS
On Thu, Sep 19, 2013 at 5:37 PM, Tanstaafl wrote: > On 2013-09-19 3:44 AM, Hinnerk van Bruinehsen >> You should definitely determine the right value for ashift on pool >> creation >> (it controls the alignment on the medium). It's an option that you afaik >> can only set >> on filesystem creation and therefore needs a restart from scratch if you >> get it >> wrong. >> According to the illumos wiki it's possible to run a mixed pool (if you >> have >> drives requiring different alignments[1]) >> If in doubt: ask ryao (iirc given the right information he can tell you >> which >> are the right options for you if you can't deduce it yourself). >> Choosing the wrong alignment can cause severe performance loss (that's not >> a ZFS issue but happened when 4k sector drives appeared and tools like >> fdisk >> weren't aware of this). > > > Yikes... > > Ok, shouldn't there be a tool or tools to help with this? Ie, boot up on a > bootable tools disk on the system with all drives connected, then let it > 'analyze' your system, maybe ask you some questions (ie, how you will be > configuring the drives/RAID, etc), then spit out an optimized config for > you? > > It is starting to sound like you need to be a dang engineer just to use > ZFS... > Just do ashift=12 and you're good to go. No need to analyze further. The reason I said that because in the future, *all* drives will have 4 KiB sectors. Currently, many drives still have 512 B sectors. But when one day your drive dies and you need to replace it, will you be able to find a drive with 512 B sectors? Unlikely. That's why, even if your drives are currently of the 'classic' 512 B ones, go with ashift=12 anyway. For SSDs, the situation is murkier. Many SSDs 'lie' about their actual sector size, reporting to the OS that their sector size is 512 B (or 4 KiB). No tool can pierce this veil of smokescreen. The only way is to do research on the Internet. IIRC, a ZFS developer has embedded -- or planned to embed -- a small database into the ZFS utilities to conclusively determine what settings will be optimal. I forgot who exactly. Maybe @ryao can pipe in (hello Richard! If you're watching this thread, feel free to add more info). Rgds, -- FdS Pandu E Poluan ~ IT Optimizer ~ • LOPSA Member #15248 • Blog : http://pepoluan.tumblr.com • Linked-In : http://id.linkedin.com/in/pepoluan
Re: [gentoo-user] Re: ZFS
>> You should definitely determine the right value for ashift on pool >> creation >> (it controls the alignment on the medium). It's an option that you afaik >> can only set >> on filesystem creation and therefore needs a restart from scratch if you >> get it >> wrong. >> According to the illumos wiki it's possible to run a mixed pool (if you >> have >> drives requiring different alignments[1]) >> If in doubt: ask ryao (iirc given the right information he can tell you >> which >> are the right options for you if you can't deduce it yourself). >> Choosing the wrong alignment can cause severe performance loss (that's not >> a ZFS issue but happened when 4k sector drives appeared and tools like >> fdisk >> weren't aware of this). > > Yikes... > > Ok, shouldn't there be a tool or tools to help with this? Ie, boot up on a > bootable tools disk on the system with all drives connected, then let it > 'analyze' your system, maybe ask you some questions (ie, how you will be > configuring the drives/RAID, etc), then spit out an optimized config for > you? I'm also interested to know the procedure for getting this right. > It is starting to sound like you need to be a dang engineer just to use > ZFS... I thought the SSD issue was completely separate from ZFS and applicable to any other filesystem as well. Someone please correct me if I'm wrong. - Grant
Re: [gentoo-user] Re: ZFS
On 2013-09-19 3:44 AM, Hinnerk van Bruinehsen You should definitely determine the right value for ashift on pool creation (it controls the alignment on the medium). It's an option that you afaik can only set on filesystem creation and therefore needs a restart from scratch if you get it wrong. According to the illumos wiki it's possible to run a mixed pool (if you have drives requiring different alignments[1]) If in doubt: ask ryao (iirc given the right information he can tell you which are the right options for you if you can't deduce it yourself). Choosing the wrong alignment can cause severe performance loss (that's not a ZFS issue but happened when 4k sector drives appeared and tools like fdisk weren't aware of this). Yikes... Ok, shouldn't there be a tool or tools to help with this? Ie, boot up on a bootable tools disk on the system with all drives connected, then let it 'analyze' your system, maybe ask you some questions (ie, how you will be configuring the drives/RAID, etc), then spit out an optimized config for you? It is starting to sound like you need to be a dang engineer just to use ZFS...
Re: [gentoo-user] Re: ZFS
Am 19.09.2013 09:47, schrieb Pandu Poluan: > Especially with SSDs. One must find out the blocksize used by his/her SSDs. > > With spinning disks, setting ashift=12 is enough since no spinning > disks have sectors larger than 2^12 bytes. > > With SSDs, one might have to set ashift=13 or even ashift=14. May I suggest that we should somehow collect all these small but important issues for reference? Wiki? Stefan
Re: [gentoo-user] Re: ZFS
On Thu, Sep 19, 2013 at 2:44 PM, Hinnerk van Bruinehsen wrote: > On Wed, Sep 18, 2013 at 09:49:40PM -0700, Grant wrote: >> > I think many folks are interested in upgrading to EXT4 with RAID from >> > an ordinary JBOD workstation(server); or better yet to ZFS on RAID. I wish >> > one of the brighter minds amongst us would put out a skeleton >> > (wiki) information page as such: >> > >> > http://wiki.gentoo.org/wiki/ZFS+RAID >> > >> > I know I have struggled with completing this sort of installation >> > several time in the last 6 months. I'm sure this (proposed) wiki page >> > would get lots of updates from the Gentoo user community. Surely, >> > I'm not qualified to do this, or it would have already been on the >> > gentoo wiki >> > >> > Much of the older X + RAID pages are deprecated, when one considers >> > the changes that accompany such an installation ( Grub2, UUID, fstab, >> > partitioning of drives, Kernel options, just to name a few). We're >> > talking about quite a bit of deviation from the standard handbook >> > installation, fraught with hidden, fatal mis-steps. >> >> Any important points or key concepts a ZFS newbie should remember when >> installing with it for the first time? >> >> - Grant > > > You should definitely determine the right value for ashift on pool creation > (it controls the alignment on the medium). It's an option that you afaik can > only set > on filesystem creation and therefore needs a restart from scratch if you get > it > wrong. > According to the illumos wiki it's possible to run a mixed pool (if you have > drives requiring different alignments[1]) > If in doubt: ask ryao (iirc given the right information he can tell you which > are the right options for you if you can't deduce it yourself). > Choosing the wrong alignment can cause severe performance loss (that's not > a ZFS issue but happened when 4k sector drives appeared and tools like fdisk > weren't aware of this). > > WKR > Hinnerk > Especially with SSDs. One must find out the blocksize used by his/her SSDs. With spinning disks, setting ashift=12 is enough since no spinning disks have sectors larger than 2^12 bytes. With SSDs, one might have to set ashift=13 or even ashift=14. Rgds, -- FdS Pandu E Poluan ~ IT Optimizer ~ • LOPSA Member #15248 • Blog : http://pepoluan.tumblr.com • Linked-In : http://id.linkedin.com/in/pepoluan
Re: [gentoo-user] Re: ZFS
On Wed, Sep 18, 2013 at 09:49:40PM -0700, Grant wrote: > > I think many folks are interested in upgrading to EXT4 with RAID from > > an ordinary JBOD workstation(server); or better yet to ZFS on RAID. I wish > > one of the brighter minds amongst us would put out a skeleton > > (wiki) information page as such: > > > > http://wiki.gentoo.org/wiki/ZFS+RAID > > > > I know I have struggled with completing this sort of installation > > several time in the last 6 months. I'm sure this (proposed) wiki page > > would get lots of updates from the Gentoo user community. Surely, > > I'm not qualified to do this, or it would have already been on the > > gentoo wiki > > > > Much of the older X + RAID pages are deprecated, when one considers > > the changes that accompany such an installation ( Grub2, UUID, fstab, > > partitioning of drives, Kernel options, just to name a few). We're > > talking about quite a bit of deviation from the standard handbook > > installation, fraught with hidden, fatal mis-steps. > > Any important points or key concepts a ZFS newbie should remember when > installing with it for the first time? > > - Grant You should definitely determine the right value for ashift on pool creation (it controls the alignment on the medium). It's an option that you afaik can only set on filesystem creation and therefore needs a restart from scratch if you get it wrong. According to the illumos wiki it's possible to run a mixed pool (if you have drives requiring different alignments[1]) If in doubt: ask ryao (iirc given the right information he can tell you which are the right options for you if you can't deduce it yourself). Choosing the wrong alignment can cause severe performance loss (that's not a ZFS issue but happened when 4k sector drives appeared and tools like fdisk weren't aware of this). WKR Hinnerk [1] http://wiki.illumos.org/display/illumos/ZFS+and+Advanced+Format+disks signature.asc Description: Digital signature
Re: [gentoo-user] Re: ZFS
On Thu, Sep 19, 2013 at 11:49 AM, Grant wrote: >> I think many folks are interested in upgrading to EXT4 with RAID from >> an ordinary JBOD workstation(server); or better yet to ZFS on RAID. I wish >> one of the brighter minds amongst us would put out a skeleton >> (wiki) information page as such: >> >> http://wiki.gentoo.org/wiki/ZFS+RAID >> >> I know I have struggled with completing this sort of installation >> several time in the last 6 months. I'm sure this (proposed) wiki page >> would get lots of updates from the Gentoo user community. Surely, >> I'm not qualified to do this, or it would have already been on the >> gentoo wiki >> >> Much of the older X + RAID pages are deprecated, when one considers >> the changes that accompany such an installation ( Grub2, UUID, fstab, >> partitioning of drives, Kernel options, just to name a few). We're >> talking about quite a bit of deviation from the standard handbook >> installation, fraught with hidden, fatal mis-steps. > > Any important points or key concepts a ZFS newbie should remember when > installing with it for the first time? > > - Grant > Plan carefully how you are going to create the vdev's before you add them to a pool. Once a vdev has been created and added to a pool, you can't ever un-add and/or replace them. (You always can replace a component of a vdev -- e.g., if one physical drive fails -- but you can't remove a vdev in its entirety). Rgds, -- FdS Pandu E Poluan ~ IT Optimizer ~ • LOPSA Member #15248 • Blog : http://pepoluan.tumblr.com • Linked-In : http://id.linkedin.com/in/pepoluan
Re: [gentoo-user] Re: ZFS
> I think many folks are interested in upgrading to EXT4 with RAID from > an ordinary JBOD workstation(server); or better yet to ZFS on RAID. I wish > one of the brighter minds amongst us would put out a skeleton > (wiki) information page as such: > > http://wiki.gentoo.org/wiki/ZFS+RAID > > I know I have struggled with completing this sort of installation > several time in the last 6 months. I'm sure this (proposed) wiki page > would get lots of updates from the Gentoo user community. Surely, > I'm not qualified to do this, or it would have already been on the > gentoo wiki > > Much of the older X + RAID pages are deprecated, when one considers > the changes that accompany such an installation ( Grub2, UUID, fstab, > partitioning of drives, Kernel options, just to name a few). We're > talking about quite a bit of deviation from the standard handbook > installation, fraught with hidden, fatal mis-steps. Any important points or key concepts a ZFS newbie should remember when installing with it for the first time? - Grant
[gentoo-user] Re: ZFS
Bruce Hill happypenguincomputers.com> writes: > On Tue, Sep 17, 2013 at 02:11:33PM -0400, Tanstaafl wrote: > > > > Is there a good place to read about these kinds of tuning parameters? > > Just wondering if anyone experienced running ZFS on Gentoo finds this wiki > article worthy of use: http://wiki.gentoo.org/wiki/ZFS I think many folks are interested in upgrading to EXT4 with RAID from an ordinary JBOD workstation(server); or better yet to ZFS on RAID. I wish one of the brighter minds amongst us would put out a skeleton (wiki) information page as such: http://wiki.gentoo.org/wiki/ZFS+RAID I know I have struggled with completing this sort of installation several time in the last 6 months. I'm sure this (proposed) wiki page would get lots of updates from the Gentoo user community. Surely, I'm not qualified to do this, or it would have already been on the gentoo wiki Much of the older X + RAID pages are deprecated, when one considers the changes that accompany such an installation ( Grub2, UUID, fstab, partitioning of drives, Kernel options, just to name a few). We're talking about quite a bit of deviation from the standard handbook installation, fraught with hidden, fatal mis-steps. Lord knows the Gentoo doc team wold appreciate such a wiki installation guide, as the handbook is undergoing modernization. just a thought. James
Re: [gentoo-user] Re: ZFS wiki confusion
On Mon, Apr 1, 2013 at 9:16 AM, Neil Bothwick wrote: > On Mon, 01 Apr 2013 10:09:05 +0200, Remy Blank wrote: > > > Just ignore the section "Installing into the kernel directory (for > > static installs)" on that page, unless you have a very special install > > (but then, you probably wouldn't have to ask here). > > Yes, you only need that if you want the modules built into the > kernel. The zfs and spl sources include scripts to install to any kernel > tree, just unpack each source tarbal, cd into the appropriate directory > and run > > ./configure --enable-linux-builtin --with-linux=/usr/src/linux > ./copy-builtin /usr/src/linux > > for each. > > ah! so the 'static' is a reference to non-modular kernel builds. got it. -- Douglas J Hunley (doug.hun...@gmail.com) Twitter: @hunleyd Web: douglasjhunley.com G+: http://goo.gl/sajR3
Re: [gentoo-user] Re: ZFS wiki confusion
On Mon, 01 Apr 2013 10:09:05 +0200, Remy Blank wrote: > Just ignore the section "Installing into the kernel directory (for > static installs)" on that page, unless you have a very special install > (but then, you probably wouldn't have to ask here). Yes, you only need that if you want the modules built into the kernel. The zfs and spl sources include scripts to install to any kernel tree, just unpack each source tarbal, cd into the appropriate directory and run ./configure --enable-linux-builtin --with-linux=/usr/src/linux ./copy-builtin /usr/src/linux for each. -- Neil Bothwick I am McCoy of Bo...Damnit! I'm a doctor, not a collective! signature.asc Description: PGP signature
[gentoo-user] Re: ZFS wiki confusion
Douglas J Hunley wrote: > Do you really need to copy the files into the kernel tree? No, you don't need to do that. > which seems to pull in the daemon and the kmod so wouldn't the zfs-kmod > ebuild build against the current kernel and drop in the modules > directory all by itself much like any of the 100s of FUSE modules do? Yes, it's enough to simply emerge the packages, and "modprobe zfs" (and later add "zfs" to /etc/conf.d/modules). Works fine here. (Not sure what FUSE has to do with it, though. FUSE filesystems don't install any kernel modules.) Just ignore the section "Installing into the kernel directory (for static installs)" on that page, unless you have a very special install (but then, you probably wouldn't have to ask here). -- Remy signature.asc Description: OpenPGP digital signature
