| 1 |
On Fri, 2010-04-02 at 14:45 +0200, Volker Armin Hemmann wrote: |
| 2 |
> On Freitag 02 April 2010, meino.cramer@×××.de wrote: |
| 3 |
> > Neil Bothwick <neil@××××××××××.uk> [10-04-02 14:08]: |
| 4 |
> > > On Fri, 2 Apr 2010 13:04:53 +0200, meino.cramer@×××.de wrote: |
| 5 |
> > > > only to be sure to have understood everything correctly: |
| 6 |
> > > > Suggestion is to create for example one root partition and a swap |
| 7 |
> > > > partion. And I will create on big "rest of the disk"-partition. |
| 8 |
> > > > The last one will be subdivided with LVM into portions as needed. |
| 9 |
> > > |
| 10 |
> > > Yes. |
| 11 |
> > > |
| 12 |
> > > > Since the last big partition is big due to physical reasons (not for |
| 13 |
> > > > logical one): What will happen, if -- for example -- one portion will |
| 14 |
> > > > be not unmounted cleanly and while booting/checking fails to recover? |
| 15 |
> > > > Are all others damaged/lost? |
| 16 |
> > > |
| 17 |
> > > No, because the failure you describe is at the filesystem level. Even the |
| 18 |
> > > volume containing that filesystem will retain integrity, only the |
| 19 |
> > > filesystem itself will be corrupted. As you have left free space on the |
| 20 |
> > > volume group, you can just create a new volume, format it and copy over |
| 21 |
> > > everything you can recover from the broken filesystem before deleting it. |
| 22 |
> > |
| 23 |
> > Hi Neil, |
| 24 |
> > |
| 25 |
> > yes, sounds good, very good. |
| 26 |
> > Last question: How heavy is the performance impact of such a setup ? |
| 27 |
> |
| 28 |
> seriously lvm sounds nice. But it isn't. It easily breaks. |
| 29 |
> |
| 30 |
> You want a save setup? Go raid5 or raid6. As a bonus - you can get more space |
| 31 |
> if you need it by just adding another disk. And you are not depending on some |
| 32 |
> complex stuff to get it working. |
| 33 |
> |
| 34 |
|
| 35 |
My experience is lvm itself is quite robust and very low impact on |
| 36 |
performance. More reliable than linux software raid at least (well the |
| 37 |
raid 0 that I was using: ) - never had a problem I could trace to lvm. |
| 38 |
|
| 39 |
The only thing thats affected lvm for me were hardware errors (disk |
| 40 |
died). |
| 41 |
|
| 42 |
My experience was with raid 0, while the higher raid redundancy will |
| 43 |
shift the reliability figures back the other way. |
| 44 |
|
| 45 |
Its really down to space and management or losing space to redundancy. |
| 46 |
Yes its an extra layer on top of the raw hardware (but so is raid |
| 47 |
really) so its the flexibility thats important. |
| 48 |
|
| 49 |
BillK |
Archives