This seems to have been memory related after all. When I reduce the memory usage with -m 3000 rather than -m 3200 then the machines are stable :/
These are running on 32-bit Debian lenny without any 'large mem' patches, so is the maximum RAM per process simply 3072MB (3 x 1024) ? I thought each 32-bit app had a full 4GB memory space, just not permitted any more than that..) Cheers, Gavin.
