Re: [Slightly OT] Releasing swap space?

[Camaleón <noelamac@gmail.com>]

On Sun, 14 Aug 2011 15:37:34 +0100, AG wrote:

> On 14/08/11 15:27, Camaleón wrote:
 
>> What's your amount of physical ram?
>>
>>
> My hard ram is 3 GB (2.84 to be exact) and I gave the same amount to
> swap when I initially partitioned the HDD.

That's a fair amount of ram... I wonder why your system is in the need of 
making use of swap.

>>> Is there any value/ harm in releasing this space using something like:
>>>
>>> swapoff -a&&  swapon -a [1]
>> (...)
>>
>> No harm, but no need to do it neither, unless you have a specific
>> requirement. Swap usage is up to the kernel, just let it to manage as
>> it desires (remember the kernel's law: "unused memory is wasted
>> memory").
> 
> I wasn't aware of that law.  Thanks for the info ;-)
> 
> My response to Ivan crossed yours, so if there's no value and I also run
> the risk of meddling with the kernel's affairs, it seems wise to leave
> well enough alone, unless I have a specific need to do so and the usage
> has accumulated.

I would investigate why 3 GiB is not enough, maybe there is a background 
app that is (ab)using too much ram for any reason :-?

It just happened to me something similar a couple of days ago, but on a 
server that has 8 GiB of RAM (and 1 GiB of swap). I was copying a big 
file (~37 GiB) over the network from a windows client to the samba server 
and when it finished, I realized the server was using a small amount of 
swap (¿?) and kept it so until the next day when the server was started 
again :-)

So, who is going to say that a "/swap" partition is going to be needed 
with 8 GiB of RAM? I wouldn't, I just thought kernel makes use of all of 
the available resources are allocates them to get the best performance. 
Meaning: if you have available resources (i.e., unused swap) they will be 
used.

Greetings,

-- 
Camaleón