[Xymon] Redhat Memory Question

Mark Felder feld at feld.me
Fri Mar 20 14:12:21 CET 2015



On Thu, Mar 19, 2015, at 19:35, Root, Paul T wrote:
> I have a script that frees up those buffers that make memory look full
>           sync
>         echo 3 >/proc/sys/vm/drop_caches
>         free -mt
> 

Why would you do that? It is strongly recommended to not do that:


> Use of this file can cause performance problems.  Since it discards cached
> objects, it may cost a significant amount of I/O and CPU to recreate the
> dropped objects, especially if they were under heavy use.  Because of this,
> use outside of a testing or debugging environment is not recommended.


Page cache is not memory that is unavailable to other applications. If a
program requests more memory and there is not enough free, it will take
the page cache.



More information about the Xymon mailing list