Re: [gentoo-user] {OT} SSD instead of RAID1?

[Grant]

>>>> Is cost-savings the advantage of using CF instead of SSD?  It sounds
>>>> like it might be wiser to spend a little more (low capacity SSD drives
>>>> are pretty cheap now) and have a real storage device that doesn't need
>>>> an adapter and is much faster, can swap, etc.
>>> I assumed that you're looking at £100 or more for an SSD, as opposed to <
>>> £10 for a CF card. I didn't check those prices, however.
>>>
>>> Are SSDs really *that* much better than CF cards in terms of write cycles?
>>> (i.e. swap)
>>> How much swap are you actually using?
>>>
>>> If the box is just a NAS, then I can't see the speed of the system drive is
>>> an issue *at all*.
>>
>> They're actually workstations so I don't think I should neglect the
>> performance aspect.  Should this scheme keep the system running if the
>> HD fails?
>>
>> / SSD
>> /boot SSD
>> /home HD
>> swap HD
>>
>
> No. As I pointed out in one of my earlier posts, you can't put swap on
> the HD. It would certainly crash the system when the disk fails.
>
> Better make sure that these systems have that much RAM that they don't
> need a swap-partition. Alternatively, buy a decent SSD, not a cheap one,
> and swap on that.

OK, that's right.  How can I find out if 4GB RAM (the current amount)
is enough?  From what I understand of how Linux handles memory, it
will fill it up as quickly as possible, and then free it as necessary.
 This makes it difficult to determine how much RAM is necessary from
watching top.

I read on this list that the kernel needs *some* swap, even just a
tiny amount, to function properly.  Is that true?  If so, do you think
it would be OK to put this tiny amount of swap on a cheap SSD?

- Grant