Hello,

Within the context of a VPS environment, "dcachesize" usually refers to a resource limit imposed by the virtualization container of your virtual server. Some details on this may be found here: "https://wiki.openvz.org/UBC_auxiliary_parameters#dcachesize"

I would approach solving this from two sides. One is to contact your service provider with this error and see if they can raise the limit for you. The other would be to see what parts of your installation could be causing high consumption of resources. In particular amount of open files. I would also take a closer look at your database configuration to see if any optimizations can be performed.

Aside from this, it is difficult to suggest further remedies without additional data and troubleshooting.

Hope this helps.