Ard:
  I think current region is 128 (1 << 7) bytes. But, I agree use exponential 
bin sizes is better than linearly increasing with 128 bytes. 

  Your patch defines mPoolSizeTable as below. Its max value is 24128. When 
Granularity is 64K, the request pool size that larger than 24128 will require 
allocate Granularity size. Is it the expected result? Or expand to the value 
nearly to 64K?
STATIC CONST UINT16 mPoolSizeTable[] = {
  64, 128, 192, 320, 512, 832, 1344, 2176, 3520, 5696, 9216, 14912, 24128  // 
append 39040, 63168?
};

  Besides, could you verify this patch on the normal case that Granularity is 
always 4K and collect the memory usage info? 

Thanks
Liming
-----Original Message-----
From: Ard Biesheuvel [mailto:ard.biesheu...@linaro.org] 
Sent: Monday, February 09, 2015 12:51 AM
To: edk2-devel@lists.sourceforge.net; ler...@redhat.com; 
olivier.mar...@arm.com; roy.fr...@linaro.org; leif.lindh...@linaro.org; Justen, 
Jordan L; Tian, Feng
Subject: [edk2] [PATCH 0/6] update pool allocator to better support 64 KB 
runtime regions

This series implements an updated pool allocator that performs better in a 
situation where the boot time and runtime allocation alignment is different, 
and where either may be substantially larger than a single page.

Without these patches applied, the pool allocations (in bytes) that are served 
from the bins are as follows (on AArch64-QEMU with Intel BDS using -kernel):

LoaderData   used   3232   allocated   8192
BootSvData   used 198872   allocated 319488
RuntSvData   used  17592   allocated  32768

However, when increasing the granularity of the allocations for runtime regions 
(patches #1 and #6 applied), it becomes apparent that the current code does not 
cope well in the runtime case

LoaderData   used   3424   allocated   4096
BootSvData   used 198872   allocated 319488
RuntSvData   used  17592   allocated 524288

This series attempts to address this by changing a couple of things in the pool
allocator:
- use exponential bin sizes rather than linearly increasing with 32 bytes
- if a bin is depleted, get a block from the next bin and split it up

With all patches applied, the numbers become

LoaderData   used   3136   allocated   8192
BootSvData   used 195344   allocated 270336
RuntSvData   used  23136   allocated  65536

Note the final 'used' number has increased: this is most likely due to a pool 
allocation of > 4 KB that was formerly served by a passthrough allocation 
(i.e., a pool allocation that is backed directly by a call to AllocatePages 
()), but is now served from one of the bins.

Ard Biesheuvel (6):
  MdeModulePkg: use correct granularity when allocating pool pages
  MdeModulePkg: improve scalability of memory pools
  MdeModulePkg: use index to traverse free pool pages
  MdeModulePkg: carve pool pages into the largest chunks possible
  MdeModulePkg: serve allocations from higher-up bins if current bin is
    empty
  MdeModulePkg: use 64 KB granularity for runtime allocations on AArch64

 MdeModulePkg/Core/Dxe/Mem/Imem.h |   9 +++
 MdeModulePkg/Core/Dxe/Mem/Pool.c | 145 ++++++++++++++++++++++++++-------------
 2 files changed, 107 insertions(+), 47 deletions(-)

--
1.8.3.2


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