Re: RFC: Switching guided partitioning to LVM by default?
Geert Stappers writes: > On Sat, Aug 05, 2017 at 04:06:49PM -0400, Cyril Brulebois wrote: >> Hi, >> >> While preparing some slides for my ???News from the Debian Installer??? talk >> at DebConf17, it occured to me that we might want to reconsider the >> default here: >> >> Guided - use a whole disk >> Guided - use a whole disk with LVM >> Guided - use a whole disk with encrypted LVM >> Manual >> >> Current default is the first entry, and I think we should switch to >> second one, with LVM. >> >> If the user doesn't need to touch anything, that doesn't change much; if >> the user wants to change partitioning afterwards, LVM's flexibility is >> available. >> >> Is anyone aware of any drawbacks of switching to LVM by default? >> > > When we take LVM as default (which is fine for me) > then we should have the courage to have free PE. > So not assign all diskspace. > Advantages: > * user gets the benefit of LVM: assigning space to a file system > * quicker install ( no formatting/mkfs of whole disk ) > * no need to shrink /home so space can be used for /srv > Disavantage, in theory: > * user might miss disk space I don't really have a strong opinion about whether LVM should be on by default, but when it is, allocating all of the space seems pretty useless to me, as the ability to extend to LVs is the main advantage of using LVM, and you need spare to allocate for that. Of course, if we're going to leave some spare, that is perhaps an argument against making LVM default, since the most naive user will be upset when they can only fit 100GB of photos on their shiny new 10TB hard drive. We can either decide that they deserve to be educated at that point, in which case LVM as default is fine with me, or leave them in happy ignorance by having given them the whole disk on one partition as default. I slightly favour the latter, and offering partially-filled-LVM as the alternative, because if people actively select that option there's a chance that they'll remember the bit that told them they'll need to find out how to make things bigger if they run out of space. BTW what are other distros doing as default these days? Somewhat Off-topic: ISTR that AIX (or perhaps something from SG) of about 20 years ago would allocate only enough space for the OS at install, so you'd see that e.g. /usr was 100% full, which was initially upsetting, but wasn't a problem because if you installed additional packages it would automatically add more space to things as needed. It seemed like a really nice idea at the time, although I can imagine that having fragmented LVs might be a little annoying. They also used to copy the packages from the install media onto a spare volume, so that you didn't need to dig out the, erm, tape probably in order to install packages, which gave you something to delete when the disk was full. Perhaps we can learn from that? (but probably not quickly enough to be relevant here) Cheers, Phil. -- |)| Philip Hands [+44 (0)20 8530 9560] HANDS.COM Ltd. |-| http://www.hands.com/http://ftp.uk.debian.org/ |(| Hugo-Klemm-Strasse 34, 21075 Hamburg,GERMANY signature.asc Description: PGP signature
Re: RFC: Switching guided partitioning to LVM by default?
2017/08/06 5:07 "Cyril Brulebois" : > > Hi, > > While preparing some slides for my “News from the Debian Installer” talk > at DebConf17, it occured to me that we might want to reconsider the > default here: > > Guided - use a whole disk > Guided - use a whole disk with LVM > Guided - use a whole disk with encrypted LVM > Manual > > Current default is the first entry, and I think we should switch to > second one, with LVM. > > If the user doesn't need to touch anything, that doesn't change much; if > the user wants to change partitioning afterwards, LVM's flexibility is > available. > > Is anyone aware of any drawbacks of switching to LVM by default? > > > KiBi. This would be a source of a lot of confusion and flame wars and other back-and-forth on debian-user. Making LVM a recommended, guided option with a lot of hand-holding, sure, especially if the default includes making a MSWindows readable partition for sharing. But that is not whole disk. Forcing people to do what we think is good for them never works out well. -- Joel Rees http://reiisi.blogspot.com
Re: RFC: Switching guided partitioning to LVM by default?
On Sat, Aug 05, 2017 at 04:06:49PM -0400, Cyril Brulebois wrote: > Current default is the first entry, and I think we should switch to > second one, with LVM. I agree & yay! -- cheers, Holger signature.asc Description: Digital signature
Re: RFC: Switching guided partitioning to LVM by default?
Le samedi, 5 août 2017, 22.20:21 h EDT Geert Stappers a écrit : > When we take LVM as default (which is fine for me) > then we should have the courage to have free PE. > So not assign all diskspace. Yes. I just tried on a stretch mini.iso, if you pick "Guided - use a whole disk with LVM" , the default partitioning you get is "All files in one partition" : 254.8 Mb /boot on ext2 107.1 Gb lvm in which … 1.1 Gb of swap 106 Gb / If we go the LVM by default route, I'd at least consider making the LVM not entirely filled, and maybe also swap the default to a separate /home. Cheers, OdyX signature.asc Description: This is a digitally signed message part.
Re: RFC: Switching guided partitioning to LVM by default?
On Sat, Aug 05, 2017 at 04:06:49PM -0400, Cyril Brulebois wrote: > Is anyone aware of any drawbacks of switching to LVM by default? - It makes sharing the disk with other operating systems harder: partman requires that the LVM PVs are committed to disk before you can play around with LVs, and since "use the whole disk" creates a single whole-disk partition for the LVM PV, there will be no space left for the other operating system if that does not support Linux's LVM. A user who would wish to create a partition for an alternate operating system after going through the LVM step would have to destroy all LVM LVs, destroy the VG, destroy the PVs, change the size of the partition, and then recreate everyhing again. - Last I checked (but this may have been changed), the LVM VG created by the partitioner is given a default name, which confuses the kernel if you place a disk containing another LVM VG with that same name in the same machine. This makes recovering a system by placing its disk into a different machine needlessly complicated. - While LVM is indeed more flexible than plain partitions, it does add some overhead in terms of metadata, which is not necessarily useful if the user is only interested in installing to a single hard disk. All in all, I'm not convinced that switching this default will be a net plus for our users. -- Could you people please use IRC like normal people?!? -- Amaya Rodrigo Sastre, trying to quiet down the buzz in the DebConf 2008 Hacklab
Re: RFC: Switching guided partitioning to LVM by default?
On Sat, Aug 5, 2017 at 2:06 PM, Cyril Brulebois wrote: > Hi, > > While preparing some slides for my “News from the Debian Installer” talk > at DebConf17, it occured to me that we might want to reconsider the > default here: > > Guided - use a whole disk > Guided - use a whole disk with LVM > Guided - use a whole disk with encrypted LVM > Manual > > Current default is the first entry, and I think we should switch to > second one, with LVM. > > If the user doesn't need to touch anything, that doesn't change much; if > the user wants to change partitioning afterwards, LVM's flexibility is > available. > > Is anyone aware of any drawbacks of switching to LVM by default? > It makes it harder to share partitions with other operating systems in a dual boot setup, particularly a fat32 partition with windows is problematic, so nothing that matters. Actually in all seriousness, other than the dual boot issue doing a guided partitioning then changing things like deleting a partition is not well supported by the installer. It is seldom a problem for me these days as I preseed everything. > > > KiBi. > -- -- Ben Hildred Automation Support Services
Re: RFC: Switching guided partitioning to LVM by default?
On Sat, Aug 05, 2017 at 04:06:49PM -0400, Cyril Brulebois wrote: > Hi, > > While preparing some slides for my ???News from the Debian Installer??? talk > at DebConf17, it occured to me that we might want to reconsider the > default here: > > Guided - use a whole disk > Guided - use a whole disk with LVM > Guided - use a whole disk with encrypted LVM > Manual > > Current default is the first entry, and I think we should switch to > second one, with LVM. > > If the user doesn't need to touch anything, that doesn't change much; if > the user wants to change partitioning afterwards, LVM's flexibility is > available. > > Is anyone aware of any drawbacks of switching to LVM by default? > When we take LVM as default (which is fine for me) then we should have the courage to have free PE. So not assign all diskspace. Advantages: * user gets the benefit of LVM: assigning space to a file system * quicker install ( no formatting/mkfs of whole disk ) * no need to shrink /home so space can be used for /srv Disavantage, in theory: * user might miss disk space Groeten Geert Stappers -- Leven en laten leven
