Re: [gentoo-user] Intel SRT + SSD + SATA

[Alan McKinnon]

On 25/06/2013 23:44, Mick wrote:
> On Tuesday 25 Jun 2013 21:59:20 Alan McKinnon wrote:
>> On 25/06/2013 21:10, Mick wrote:
>>> Hi All,
>>>
>>> I am considering my options for a new rig destined to last a few years
>>> and one of the Dell machines on offer has this Intel SRT fake-raid
>>> feature, which after some cursory googling, I am not entirely sure will
>>> work with Linux.
>>
>> bah, that fake-raid. Just discard it completely, it's a way for windows
>> uses who don't have lvm-awesomeness to have big drives and not have to
>> do anything to get it.
>
> I think it is used to RAID the SSD onto the hard drive, so that it can be
> replicated onto a new SSD if/when the original goes bad.

This is a laptop right?

That makes no sense - when you mirror RAID an SSD onto a spinning disk,
you get a combined drive the size of the spinning disk and the SSD
becomes a fashion accessory. Which is why Dell usually disable RAIDing
an SSD and regular disk in the purchase options

>
>
>> Just use lvm and/or software raid to do the job right. You will not
>> regret using the appropriate tool for the job like this.
>
> OK, so dmraid and mdadm will do the same for Linux?

Yes

>
> How do people mirror their SD onto the SATA, or what is the recommended way to
> safeguard the SSD installed OS?

You copy it. You do not raid it. With two disks, just rsync over
whatever you need whenever you need to do it.

Unless that is, Dell's website is using the PR/Marketing definition of
what RAID is. By definition, no-one that ever reads this mailing list
can understand that definition

>
>
>>> As a side issue, I am not sure whether to fork out for an i7 Haswell, or
>>> go for good ol' AMD FX-8350 ...
>>>
>>> Is the single thread i7 superiority going to trump AMDs 8 real cores for
>>> web development, image editing and browsing activities?
>>
>> Your cell phone will cope with that work load just fine
>
> Ha!  I'm still using an old Nokia feature phone and I mostly use it to make
> telephone calls!  O_O
>
>
>> Don't stress about it, your question is on the order of magnitude of
>> wondering if 5 horses or 4 camels are better for carrying one paper bag
>> of groceries home from the supermarket. The truth is, the basket in
>> front of granny's bicycle is perfectly adequate, and probably faster too
>
> LOL!!
>
> So, you're saying that other than at compile time I won't notice the
> difference?

You will notice the grunt those i7s can deliver when you start to do
this (sort of typical for mine...):

3 virtualbox vms running, 1 Windows for IE and Office
30 tabs open in firefox
emerge world going on set to -j32 -l8
30-odd konsole tabs open, often more than half tailing a log file at
 more than 200 lines a minute
the usual desktop apps (mail, skype, movie playing in one corner)

I sort of just keep loading it up till I run out of things to leave
open, and never notice the difference. This is an 8 core i7 with 16G RAM
and 128G SSD - complete total overkill for any rational usage, even a
busy devops sysadmin - but we get good prices on the company corporate
account

It all comes down to what you really *need* as opposed to how much
techie-bling you *want* :-)

-- 
Alan McKinnon
alan.mckinnon@×××××.com