ngx_slab_alloc() failed: no memory in cache keys zone "zone-xyz"

[jakubp]

> It does so - if an allocation of a cache node fails, this will 
> trigger a forced expiration of a cache node, and then tries to 
> allocate a node again.  This is more an emergency mechanism 
> though (and not guaranteed to work, as another allocation may 
> fail, too), hence alerts are logged in such cases.
> 

Thanks for the information. It indeed helps my use case. For now I'll
disable the meassges.

Kuba

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,237829,249945#msg-249945