on 2/1/2008 4:33 PM Dean Maluski spake the following:
On Fri, 2008-02-01 at 16:11 -0800, nate wrote:
Dean Maluski wrote:
I've googled this question without a great deal of information. Of couse will be creating RAID0 swap but leaving that out of the question for obvious reasons.
You really should use anything but RAID 0 for swap. If you need to swap and that device is dead then your system is hosed.
At one point I read that you can get RAID0-"like" performance by having multiple swap partitions on multiple devices and mounting them with the same priority(mount option pri=(some number)). It (was/is) supposed to stripe the swap partitions. Not sure if that ever worked, though I have configured systems over the years to use matching swap priorities, never really looked to see if it was doing what I expected though.
Yeah, from swapon(2): [..] If two or more areas have the same priority, and it is the high-est priority available, pages are allocated on a round-robin basis between them.
nate
OK, not really an answer to my hot spare question. What I read sounds similar to what you state that if you create multiple swap partions the system will create a raid0 of it. So what is the recommendation? create 1 swap partition on one drive?
It depends. If you are going to create LVM over the large raid5 partition you could put the swap there. Or you could create a raid 1 the same way you create the /boot partition. If the system is properly sized, swap is less of a performance issue anyway.