jmb
/
hardened_malloc
mirror of https://github.com/GrapheneOS/hardened_malloc.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

limit precision for fragmentation in table

pull/87/head
Daniel Micay 2019-06-12 13:28:03 -04:00
parent 12525f2861
commit 37474e117c
2 changed files with 46 additions and 46 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

90
README.md
View File

@ -367,41 +367,41 @@ preliminary set of values.
| size class | worst case internal fragmentation | slab slots | slab size | internal fragmentation for slabs | | size class | worst case internal fragmentation | slab slots | slab size | internal fragmentation for slabs |
| - | - | - | - | - | | - | - | - | - | - |
| 16 | 93.75% | 256 | 4096 | 0.0% | | 16 | 93.75% | 256 | 4096 | 0.0% |
| 32 | 46.875% | 128 | 4096 | 0.0% | | 32 | 46.88% | 128 | 4096 | 0.0% |
| 48 | 31.25% | 85 | 4096 | 0.390625% | | 48 | 31.25% | 85 | 4096 | 0.390625% |
| 64 | 23.4375% | 64 | 4096 | 0.0% | | 64 | 23.44% | 64 | 4096 | 0.0% |
| 80 | 18.75% | 51 | 4096 | 0.390625% | | 80 | 18.75% | 51 | 4096 | 0.390625% |
| 96 | 15.625% | 42 | 4096 | 1.5625% | | 96 | 15.62% | 42 | 4096 | 1.5625% |
| 112 | 13.392857142857139% | 36 | 4096 | 1.5625% | | 112 | 13.39% | 36 | 4096 | 1.5625% |
| 128 | 11.71875% | 64 | 8192 | 0.0% | | 128 | 11.72% | 64 | 8192 | 0.0% |
| 160 | 19.375% | 51 | 8192 | 0.390625% | | 160 | 19.38% | 51 | 8192 | 0.390625% |
| 192 | 16.145833333333343% | 64 | 12288 | 0.0% | | 192 | 16.15% | 64 | 12288 | 0.0% |
| 224 | 13.839285714285708% | 54 | 12288 | 1.5625% | | 224 | 13.84% | 54 | 12288 | 1.5625% |
| 256 | 12.109375% | 64 | 16384 | 0.0% | | 256 | 12.11% | 64 | 16384 | 0.0% |
| 320 | 19.6875% | 64 | 20480 | 0.0% | | 320 | 19.69% | 64 | 20480 | 0.0% |
| 384 | 16.40625% | 64 | 24576 | 0.0% | | 384 | 16.41% | 64 | 24576 | 0.0% |
| 448 | 14.0625% | 64 | 28672 | 0.0% | | 448 | 14.06% | 64 | 28672 | 0.0% |
| 512 | 12.3046875% | 64 | 32768 | 0.0% | | 512 | 12.3% | 64 | 32768 | 0.0% |
| 640 | 19.84375% | 64 | 40960 | 0.0% | | 640 | 19.84% | 64 | 40960 | 0.0% |
| 768 | 16.536458333333343% | 64 | 49152 | 0.0% | | 768 | 16.54% | 64 | 49152 | 0.0% |
| 896 | 14.174107142857139% | 64 | 57344 | 0.0% | | 896 | 14.17% | 64 | 57344 | 0.0% |
| 1024 | 12.40234375% | 64 | 65536 | 0.0% | | 1024 | 12.4% | 64 | 65536 | 0.0% |
| 1280 | 19.921875% | 16 | 20480 | 0.0% | | 1280 | 19.92% | 16 | 20480 | 0.0% |
| 1536 | 16.6015625% | 16 | 24576 | 0.0% | | 1536 | 16.6% | 16 | 24576 | 0.0% |
| 1792 | 14.229910714285708% | 16 | 28672 | 0.0% | | 1792 | 14.23% | 16 | 28672 | 0.0% |
| 2048 | 12.451171875% | 16 | 32768 | 0.0% | | 2048 | 12.45% | 16 | 32768 | 0.0% |
| 2560 | 19.9609375% | 8 | 20480 | 0.0% | | 2560 | 19.96% | 8 | 20480 | 0.0% |
| 3072 | 16.634114583333343% | 8 | 24576 | 0.0% | | 3072 | 16.63% | 8 | 24576 | 0.0% |
| 3584 | 14.2578125% | 8 | 28672 | 0.0% | | 3584 | 14.26% | 8 | 28672 | 0.0% |
| 4096 | 12.4755859375% | 8 | 32768 | 0.0% | | 4096 | 12.48% | 8 | 32768 | 0.0% |
| 5120 | 19.98046875% | 8 | 40960 | 0.0% | | 5120 | 19.98% | 8 | 40960 | 0.0% |
| 6144 | 16.650390625% | 8 | 49152 | 0.0% | | 6144 | 16.65% | 8 | 49152 | 0.0% |
| 7168 | 14.271763392857139% | 8 | 57344 | 0.0% | | 7168 | 14.27% | 8 | 57344 | 0.0% |
| 8192 | 12.48779296875% | 8 | 65536 | 0.0% | | 8192 | 12.49% | 8 | 65536 | 0.0% |
| 10240 | 19.990234375% | 6 | 61440 | 0.0% | | 10240 | 19.99% | 6 | 61440 | 0.0% |
| 12288 | 16.658528645833343% | 5 | 61440 | 0.0% | | 12288 | 16.66% | 5 | 61440 | 0.0% |
| 14336 | 14.278738839285708% | 4 | 57344 | 0.0% | | 14336 | 14.28% | 4 | 57344 | 0.0% |
| 16384 | 12.493896484375% | 4 | 65536 | 0.0% | | 16384 | 12.49% | 4 | 65536 | 0.0% |
The slab allocation size classes end at 16384 since that's the final size for The slab allocation size classes end at 16384 since that's the final size for
2048 byte spacing and the next spacing class matches the page size of 4096 2048 byte spacing and the next spacing class matches the page size of 4096
@ -423,18 +423,18 @@ retaining the isolation.
| size class | worst case internal fragmentation | slab slots | slab size | internal fragmentation for slabs | | size class | worst case internal fragmentation | slab slots | slab size | internal fragmentation for slabs |
| - | - | - | - | - | | - | - | - | - | - |
| 20480 | 19.9951171875% | 2 | 40960 | 0.0% | | 20480 | 20.0% | 2 | 40960 | 0.0% |
| 24576 | 16.66259765625% | 2 | 49152 | 0.0% | | 24576 | 16.66% | 2 | 49152 | 0.0% |
| 28672 | 14.2822265625% | 2 | 57344 | 0.0% | | 28672 | 14.28% | 2 | 57344 | 0.0% |
| 32768 | 12.4969482421875% | 2 | 65536 | 0.0% | | 32768 | 12.5% | 2 | 65536 | 0.0% |
| 40960 | 19.99755859375% | 1 | 40960 | 0.0% | | 40960 | 20.0% | 1 | 40960 | 0.0% |
| 49152 | 16.664632161458343% | 1 | 49152 | 0.0% | | 49152 | 16.66% | 1 | 49152 | 0.0% |
| 57344 | 14.283970424107139% | 1 | 57344 | 0.0% | | 57344 | 14.28% | 1 | 57344 | 0.0% |
| 65536 | 12.49847412109375% | 1 | 65536 | 0.0% | | 65536 | 12.5% | 1 | 65536 | 0.0% |
| 81920 | 19.998779296875% | 1 | 81920 | 0.0% | | 81920 | 20.0% | 1 | 81920 | 0.0% |
| 98304 | 16.6656494140625% | 1 | 98304 | 0.0% | | 98304 | 16.67% | 1 | 98304 | 0.0% |
| 114688 | 14.284842354910708% | 1 | 114688 | 0.0% | | 114688 | 14.28% | 1 | 114688 | 0.0% |
| 131072 | 12.499237060546875% | 1 | 131072 | 0.0% | | 131072 | 12.5% | 1 | 131072 | 0.0% |
The `CONFIG_LARGE_SIZE_CLASSES` option controls whether large allocations use The `CONFIG_LARGE_SIZE_CLASSES` option controls whether large allocations use
the same size class scheme providing 4 size classes for every doubling of size. the same size class scheme providing 4 size classes for every doubling of size.

2
calculate_waste.py
View File

@ -49,7 +49,7 @@ for size, slots, fragmentation in zip(size_classes, size_class_slots, fragmentat
used = size * slots used = size * slots
real = page_align(used) real = page_align(used)
print("| ", end='') print("| ", end='')
print(size, str(fragmentation) + "%", slots, real, str(100 - used / real * 100) + "%", sep=" | ", end=" |\n") print(size, f"{fragmentation:.4}%", slots, real, str(100 - used / real * 100) + "%", sep=" | ", end=" |\n")
if len(argv) < 2: if len(argv) < 2:
exit() exit()