How to reduce cached memory?

[Adrian Joian]

Hello,

Well, if you really want to decrease cache levels you could at schedule
at random times the following command:
echo 1 > /proc/sys/vm/drop_caches

Adrian JOIAN
fedoraproject.ro

Chris Tyler wrote:
> On Fri, 2009-02-06 at 23:57 +0100, Joshua C. wrote:
>   
>> I have kde 4.2 and f9. After 2+ hours on my computer it has about
>> 1,4GB cached memory. I don't see him releasing this memory after time.
>> I know it comes from the apps being open but it seems the kernel
>> "never" releases the memory after the app terminates. How to make the
>> kernel free this memory? I've seen similar cases with kde 3.5.10 and
>> f8 and f7. I know kde eats memory but this is too much. Who caches so
>> much of it? Why?
>>
>> The mashine has 2,6 GB RAM (still x86) and 512mb swap which is rarely
>> used (~ 50mb at most) and combined cached + app memory totals about 2
>> gb.
>>     
>
> Hi Joshua,
>
> Memory is being used for cache basically because it's not being used for
> anything else. The kernel will gladly use that memory for other purposes
> when it's needed -- but until then, there's no harm in keeping disk data
> around in otherwise-unused memory just in case it's needed later.
>
> This is why the "free" command shows a "-/+ buffers/cache" line, which
> shows you what the memory picture is without the cache (i.e., the memory
> that is truly available when needed):
>
>   $ free
>                total     used    free  shared buffers cached
>   Mem:       4061388  3796632  264756       0  259244 570224
>   -/+ buffers/cache:  2967164 1094224
>   Swap:      4194296  2092276 2102020
>
>
> -Chris
>
>