It looks like you are pushing your nodes far harder than the defaults allow, and far harder than they can cope:
The default for this is 2 and increasing it is not recommended.
The default for this is 2 and increasing it is not recommended.
The default for this is 2 and increasing it is not recommended.
The default for this is 4 and increasing it is not recommended.
The default for this is 40mb; increasing it is ok if your nodes can cope with the increase, but the evidence indicates that 250mb is far too high for your warm nodes.