On Sun, 12 Aug 2012 14:11:37 -0400 Allan Gottlieb <gottl...@nyu.edu> wrote:
> On Fri, Aug 10 2012, Alan McKinnon wrote: > > > On Fri, 10 Aug 2012 10:25:51 -0400 > > Allan Gottlieb <gottl...@nyu.edu> wrote: > > > >> I am getting a new laptop from dell that will dual boot windows (in > >> case I need dell maintenance) and gentoo (real work). I have done > >> this often, but there are three new aspects this time. > >> > >> 1. ssd. > >> 2. new udev (/usr part of boot partition?) > >> 3. grub2. > > > > I have one of those. But I decided to stick with traditional DOS > > partitioning style and grub instead of GPT and grub2. > > I am leaning toward traditional partitioning, but with grub2. Do > those two not mix well? I've never really used grub2 myself (can't see the point until I have no other option than GPT and EFI), but AFAIK MBR and grub2 isn't a problem. It might not be default, but it isn't a problem > > >> The laptop will have a 256GB ssd. Can I partition it the same as I > >> would have for an hd? Are there extra alignment considerations? > > > > I don't know of any special partition considerations. Just start at > > the 1M mark and align on 4096 like you would for spinning disks. > > Dell normally has a special partition of size > 40MB starting at > sector 63. Presumably I ignore that one. I would then align the > used-only-for-dell-diagnostics windows partition and all linux > partitions at multiples of 4096 Correct > > > What you will need is TRIM support and for that you use ext4. Just > > add "discard" to the mount options for the ext4 volumes. > > Ah so I will now be using ext4. The mount man page says trim is off > by default waiting for more testing. But I will try it. I think that man page is badly out of date (unless the ext4 devs understand "testing" to mean something very different to what you and I understand) > > > You also don't need an IO scheduler - ssd access is random like > > RAM, no heads moving in and out so no sector ordering to worry > > about. Configure the scheduler as NOOP in kernel config if all > > drives are ssd's > > I believe dell with be "throwing in" a removable spinning disk that > can be user swapped with the dvd so I should probably keep the I/O > scheduler. You can set the scheduler per-device too, more info here: https://wiki.archlinux.org/index.php/Solid_State_Drives#I.2FO_Scheduler Someone else reported though that Deadline scheduler can actually performs better, I also read that somewhere. Maybe you should do some initial tests yourself before deciding -- Alan McKinnon alan.mckin...@gmail.com
