[GTALUG] Swap and Hibernate on SSDs
rreiter91 at gmail.com
Sat Jan 27 10:09:33 EST 2018
On January 27, 2018 8:49:15 AM EST, Giles Orr via talk <talk at gtalug.org> wrote:
>In the early days of SSDs, there was a lot of talk in the Linux
>that you shouldn't have a swap partition on an SSD. An indirect side
>effect of that is that it becomes impossible to suspend-to-disk (aka
>"hibernate") on a SSD-only system. Although I suppose that you could
>the swap partition and set swappiness to 0. So I have a new SSD
>and was wondering the current state of these things:
I'm still tweaking/breaking (in) my new SSD desktop system myself. I took Hugh's advice and did some research on TRIM.
This link has lots of info.
My observations so far.
>- is it considered okay to have a swap partition on an SSD drive?
Yes, it's getting to be an inevitability. The key is to optimize the system to minimize the number of writes. ie. config w/ noatime to reduce writing all of the files access times to the drive. Some questions around that tho. Later kernels use relatime as a default middle ground.
Kernels 4+ have lazyatime available.
>- how should I set the swappiness?
That all depends on the operational stress factors. I think that on an average desktop, the default is fine.
>- is it considered okay to hibernate to an SSD?
Just from what I've read so far, if you keep to the convention of 2x(ram) for the swap you shouldn't have any problems.
Again, from what I've read recently, the general feeling is that an enterprise SSD, capable of >50gb writes in a day, is as virtually stable as a standard HDD. Consumer SSD's are considered the same if writes =<20gb a day.
>gilesorr at gmail.com
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