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When I Build the project,
the compilation tool didn't show any message about the memory.
First, I only use the onchip memory, the system show the message.
"ld: region onchip_mem is full (hello_world_0.elf section .text). Region needs to be 16516 bytes larger. hello_world_0 line 0 1269343999031 36
ld: section .bss [02012054 -> 0201215b] overlaps section .text [020101c8 -> 0201e083] hello_world_0 line 0 1269343999031 39
ld: section .rodata [02010020 -> 02010547] overlaps section .except
but, I builded the flesh memory to cover the part.
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Kingace9000, onchip memory is really not big enough for the project with a lot of modules and source files (like the Simple Socket Server template, for example). So you need to place more onchip memory (but it is not good for FPGA resource economy), or to add external memory (DDR, flash or other).
When you add external memory, after creating a NIOS software project for your hardware design (in NIOS II IDE utility) right-click on <your project name>_syslib[<your system name>] in Projects tab, select "Properties", when select "System library" and assign sections to memory device you need. Maybe, you should add SRAM to your hardware project?
You can check this out in altera standard design examples - they often use DDR or SRAM to store content.
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