github/acrn-hypervisor
1
0
Fork 0
mirror of https://github.com/projectacrn/acrn-hypervisor.git synced 2025-09-05 10:50:43 +00:00
Code Issues Projects Releases Wiki Activity

dm: use hugetlb by default

Browse Source 
use hugetlb to set vm memory by default.

Signed-off-by: Li, Fei1 <fei1.li@intel.com>
This commit is contained in:
Li, Fei1
2018-06-29 10:54:16 +08:00
committed by lijinxia
parent 136d5c30fb
commit 652e37e908
6 changed files with 27 additions and 46 deletions
Download Patch File Download Diff File Expand all files Collapse all files

42
doc/getting_started/index.rst
View File

@@ -330,38 +330,26 @@ Set up Reference UOS
Device Manager memory allocation mechanism
==========================================
There are two Device Manager memory allocation mechanisms available:
The ACRN Device Manager (DM) virtual memory allocation uses the HugeTLB mechanism.
(You can read more about `HugeTLB in the linux kernel <https://linuxgazette.net/155/krishnakumar.html>`_
for more information about how this mechanism works.)
- Contiguous Memory Allocator (CMA), and
- Huge Page Tables (HugeTLB). HugeTLB is the default.
For hugeTLB to work, you'll need to reserve huge pages:
To choose CMA, do the following:
- For a (large) 1GB huge page reservation, add ``hugepagesz=1G hugepages=reserved_pg_num``
(for example, ``hugepagesz=1G hugepages=4``) to the SOS cmdline in
``acrn.conf`` (for EFI)
1) Add ``cma=reserved_mem_size@recommend_memory_offset-0``, (for example
``cma=2560M@0x100000000-0``) to the SOS cmdline in ``acrn.conf``
- For a (smaller) 2MB huge page reservation, after the SOS starts up, run the
command::
2) Start ``acrn-dm`` *without* the ``-T`` option
echo reserved_pg_num > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
To support HugeTLB, do the following:
1) Do huge page reservation
- For 1G huge page reservation, add ``hugepagesz=1G hugepages=reserved_pg_num``
(for example, ``hugepagesz=1G hugepages=4``) to the SOS cmdline in
``acrn.conf`` (for EFI)
- For 2M huge page reservation, after the SOS starts up, run the
command::
echo reserved_pg_num > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
.. note::
You can use 2M reserving method to do reservation for 1G page size, but it
may fail. For an EFI platform, you may skip 1G page reservation
by using a 2M page, but make sure your huge page reservation size is
large enough for your usage.
2) Start ``acrn-dm`` *with* the ``-T`` option.
.. note::
You can use 2M reserving method to do reservation for 1G page size, but it
may fail. For an EFI platform, you may skip 1G page reservation
by using a 2M page, but make sure your huge page reservation size is
large enough for your usage.
Build ACRN from Source
**********************