Re: Can cachesize be too big?

[Jeff Leung <jeffleung@mac.com>]

Oops, I meant we are using OpenLDAP 2.1.22.

On 1/30/04 11:11 AM, "Jeff Leung" <jeffleung@mac.com> wrote:

> Hi,
> 
> Is it possible to have a BerkeleyDB cache size (set by set_cachesize in
> DB_CONFIG) be TOO big? For example, if the cachesize is greater than
> physical memory? Or for that matter, total system memory (swap + physical)?
> 
> We have two identical machines with 2GB of physical memory and 2GB of swap
> (4GB total).
> 
> Both machines running OpenLDAP 2.1.25 + BerkeleyDB 4.1.25-1
> Machine A:
> slapd-1:  cachesize=500MB
> slapd-2:  cachesize=500MB
> slapd-3:  cachesize=1GB
> Total:     2GB
> 
> Machine B:
> slapd-1:  cachesize=500MB
> slapd-2:  cachesize=500MB
> slapd-3:  cachesize=1GB
> slapd-4:  cachesize=500MB
> slapd-5:  cachesize=500MB
> slapd-6:  cachesize=1GB
> slapd-7:  cachesize=500MB
> slapd-8:  cachesize=500MB
> slapd-9:  cachesize=1GB
> slapd-10: cachesize=500MB
> slapd-11: cachesize=500MB
> slapd-12: cachesize=1GB
> Total:     6GB
> 
> Machine A is rock solid, whereas Machine B craps out daily (some instances
> will shoot up to 100% cpu, prompting a kill and db_recover).
> 
> Would the fact that the total amount of cachesize required for Machine B is
> greater than the total amount of memory on the system be a possible culprit?
> I don't think I have ever actually seen the memory usage reach max capacity
> (or even close), so I would guess no, but is it a possibility?
> 
> Thanks.

-- 
Jeff
// Diplomacy is the art of saying 'nice doggy'
// until you can find a rock.