Suggested memory allocation for memcached

[howard chen]

On 12/16/06, Ask Bjørn Hansen <ask at develooper.com> wrote:
>
> On Dec 16, 2006, at 2:08, howard chen wrote:
>
> > for example,
> >
> > I have 2GB ram, I have the following software run on the same server:
> >
> > 1. Apache 2
> > 2. MySQL 5
> > 3. Memcached
> >
> > How much memory I should allocate the Memcached?
>
> The question really doesn't make much sense without more context.
>
> Find however much memory you have available when you are running your
> application and use that (be sure to count however much memory you
> need for the kernel page cache when you calculate "available memory").
>
> You could start with very little (say 128MB) and then monitor how
> much you are using it.  For some applications it might be fine, for
> others it'll be completely unusable.
>
>
>   - ask
>
> --
> http://develooper.com/ - http://askask.com/
>
>
>

The problem is:

If memcached is always full of memory and need to swap out the old
data, is this a good situation?

That said, under how many % of hit is considered as the memory is not enougth.

Thanks.