Re: Summary: Moving /tmp to tmpfs makes it useless
Tollef Fog Heen wrote:
> > On Sun, Jun 10, 2012 at 07:46:57PM +0200, Stephan Seitz wrote:
> > > On Sun, Jun 10, 2012 at 07:12:11PM +0200, Tollef Fog Heen wrote:
> > > >]] Stephan Seitz
> > > >>Will Wheezy support SSDs out of the box with all trimming functions,
> > > >>even if your SSD partition is using LUKS and LVM?
> > > >Depends on what you mean by out of the box. I suspect you still need
> > > >to
> > > >turn on discard support (since it has security implications). It does
> > > >not require extra packages or patches.
> > > Well, nice to hear, but I thought, discard was needed in all layers,
> > > so in my example in LUKS, then in LVM and then in the filesystem. Or
> > > is his only a function you activate via hdparm?
> > It's available in all layers, but as Tollef said it's manual. (In crypttab
> > most
> > likely, because that's commonly the lowest layer.)
> You need to enable it in all layers (fstab, crypttab, lvm.conf), yes.
For now you shouldn't use discard option with SSDs, it's bad for
performance. Better is to run fstrim periodically.