Re: vmalloc allocates less memory in 1GB system...

[Ravi K <kravi26@yahoo.com>]

> What are the limits of vmalloc? How can I allocate
> (for example) 256 MB of
> memory?

The virtual address space used by vmalloc() is in the
range of VMALLOC_START and VMALLOC_END. If
CONFIG_HIGMEM is defined while building the kernel (it
will be, if the machine has more than 1GB memory), and
the PAGE_OFFSET is the default value of 0xc0000000,
this range is approximately 0xf8000000 to 0xfe000000.
This is about 96MB.


Without tweaking some kernel parameters like
MAXMEM_PFN, I don't think you can allocate more memory
using vmalloc() on machines with 1GB or more memory.

-Ravi.

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