Bochs memory messages

teodori · **Joined:** Wed Nov 14, 2012 4:55 pm **Posts:** 103

Hello, I see some messages in bochs and I don't understand them. I assume it's about memory usage.
What does this mean?

Code:

00005248076i[MEM0 ] allocate_block: block=0x18 used 0x3 of 0x800

Combuster · **Posted:** Thu Feb 13, 2014 12:04 pm

Code:

$ find -iname "*.cc" | xargs grep -n "allocate_block:"
./memory/misc_mem.cc:218:          BX_INFO(("allocate_block: block=0x%x, replaced 0x%x",   
./memory/misc_mem.cc:223:        BX_INFO(("allocate_block: block=0x%x used 0x%x of 0x%x",
./memory/misc_mem.cc:235:  BX_DEBUG(("allocate_block: used_blocks=0x%x of 0x%x", BX_MEM_THIS used_blocks, max_blocks));

Code:

#if BX_LARGE_RAMFILE
  /* 
   * Match block to vector address
   * First, see if there is any spare host memory blocks we can still freely allocate
   */

Bochs uses lazy allocation of memory, so everytime you access a new block of RAM, it'll allocate one. In this case, support for Guest RAM > Host RAM is enabled which can swap out pages to disk when they're not used, which in turn means additional log information because it's fairly new.

teodori · **Joined:** Wed Nov 14, 2012 4:55 pm **Posts:** 103

Ok so thoses messages are related to the emulator and not to the OS. I thought they showed up because I did an error in my memory manager.
Thank you

teodori · **Joined:** Wed Nov 14, 2012 4:55 pm **Posts:** 103

Are those messages usefull for debug? What does block mean? And what do the numbers tell me there?

Code:

[MEM0 ] allocate_block: block=0x10 used 0x3 of 0x200

Combuster · **Posted:** Sat Apr 05, 2014 2:55 am

I can guess, but to give an accurate answer I will have to look at the source again, which is something you could do in my place.

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Bochs memory messages

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