Re: a new install - - - putting the system on raid
From: Pascal Hambourg <hidden>
Date: 2022-06-23 22:28:13
Le 23/06/2022 à 23:39, Wols Lists a écrit :
On 23/06/2022 19:54, Pascal Hambourg wrote:quoted
quoted
If you set the fstab priorities to the same value, you get a striped raid-0 for free.Without any redundancy. What is the point of setting up RAID1 for all the rest and see your system crash pitifully when a drive fails because half of the swap suddenly becomes unreachable ?Why would it crash?
Do you really believe a program can lose some of its data and still behave as if nothing happened ? If that were true, then why not just discard data instead of swap them out when memory is short ?
Firstly, the system shouldn't be swapping. MOST systems, under MOST workloads, don't need swap.
Conversely, some systems, under some workloads, do need swap. And when they do, swap needs to be as reliable as any other storage space.
And secondly, the *system* should not be using swap. User space, yes. So a bunch of running stuff might crash. But the system should stay up.
Firstly, the *system* is not only the kernel. Many user space processes are part of the *system*. Secondly, you were the one who wrote: "/tmp - is usually tmpfs nowadays, if you need disk backing, just make sure you've got a big-enough swap (tmpfs defaults to half ram, make it bigger and let it swap)."
Raid is meant to protect your data. The benefit for raiding your swap is much less, and *should* be negligible.
No, this is what backup is meant to. RAID does not protect your data against accidental or malicious deletion or corruption. RAID is meant to provide availabity. The benefit of having everything including swap on RAID is that the system as a whole will continue to operate normally when a drive fails.