[OSX-Users] Re: RAM for a macbook

[Christopher Gutteridge]

Sometimes when I need to preserve the battery I use

% pmset -a hibernatemode 1

which sets it to actually write the memory to disk when it goes to 
sleep. You get the annoying wait for it to start up again (20-30 
seconds) but it's great if you want to preserve the current desktop 
setup without draining the battery. You can restore it to the normal 
mode with

% pmset -a hibernatemode 3

and view the current setting with

% pmset -g

I don't know how to set this option via the GUI.

On 23/08/10 10:51, Steve Harris wrote:
> On 2010-08-23, at 03:08, Hugh Glaser wrote:
>
>    
>> I hesitate to venture into such informed company, and not wholly agree with
>> a tiny bit of it, but... :-)
>>
>> On 19/07/2010 18:13, "Steve Harris"<swh at ecs.soton.ac.uk>  wrote:
>>
>>      
>>> On 2010-07-19, at 17:44, Marcus Cobden wrote:
>>>        
>>>> On 19 Jul 2010, at 17:33, Christopher Gutteridge wrote:
>>>>
>>>>          
>>>>> My macbook (White, 2Ghz) is feeling a bit slow and I think it would benefit
>>>>> from an increase in RAM. (currently 1GB)
>>>>>
>>>>> How much can I upgrade it to?
>>>>>            
>>>> Depends on the model:
>>>> https://secure.wikimedia.org/wikipedia/en/wiki/Macbook#Model_specifications
>>>>
>>>>          
>>>>> Is it worth it?
>>>>>            
>>>> Yes.
>>>>
>>>> I may have imagined it, but I got the feeling that my battery lasted a little
>>>> less longer with more RAM. I have no idea if this differs between brands of
>>>> RAM though.
>>>>          
>>> That's normal, it's because the disk is doing less work.
>>>        
>> Only so far.
>> If you can afford shitloads of RAM, then the battery will spend its time
>> powering the extra RAM that is not being used.
>> Probably not a problem.
>> But the battery life when asleep may be reduced, as it is keeping the RAM
>> alive.
>>      
> That's probably true, yes. Current generation machines seem to be very efficient when asleep though. I didn't notice any difference on my macbook pros going 2->4, but I wasn't looking out for it. I did notice the difference in runtime though.
>
>    
>> Mind you, this was a few years ago, and I am sure that someone will tell me
>> that it is no longer true.
>>
>> But a 1->2 upgrade is likely to be stunning.
>>      
> Also a 2->4 upgrade is well worth it, in my experience.
>
>    
>> It is possible that maybe 0.75 Gig of the memory is used most of the time
>> (system, etc.), and so you will then get 5 times that memory for the other
>> stuff.
>> And if you can get to 4 Gig (I wrote Meg first time, as I still remember
>> machines with K!), then the machine will be better and is likely to last
>> longer without additional cost or upgrade hassle.
>>
>> One of the things that has changed over the last few years is how long
>> machines last. Used to be a couple of years, but a machine like yours, that
>> was bought a year or two (or more?) ago, will still be good for maybe 3 or 4
>> more years, unless you are doing fancy graphics processing (or similar) on
>> it.
>>
>> Laptops tend to be hard to upgrade bits of memory, so put the most you can
>> afford in now.
>>      
> That seem to vary a lot, the difficulty of upgrading RAM in last 3 Mac laptops I've had were: trivial (no screwdriver needed), almost impossible, small amount of screwdriver work needed - in chronological order.
>
> - Steve
>    

-- 
Christopher Gutteridge -- http://id.ecs.soton.ac.uk/person/1248

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