Houdini 1.5 with Large Page support and 8-cores for w32
Posted: Sun Dec 19, 2010 9:28 pm
I've now corrected the inadvertently disabled large page support in Houdini 1.5, and, at popular request, also increased the maximum number of threads for the 32-bit version to 8.
The dowload package that is available at http://www.cruxis.com/chess/houdini.htm contains these 2 changes:
- large page support (works both in 64-bit and 32-bit Windows)
- 32-bit version with support of up to 8 cores instead of 4
If you don't need large page support or 32-bit 8-cores version, there is no reason to download the new files. The new engines produce *exactly* the same output as the old.
For the large page support, there is a hidden command "lp" that will show you how much large page memory is available in different sizes.
Simply run the engine by double-clicking on the executable, then enter the command lp. This will produce for example the following output:
In this example on a 8 GB server immediately after reboot there is nearly 3 GB of large pages available. The results show that the maximum large page hash is 2048 MB.
I've done some speed comparisons:
- For 512 MB hash on 32-bit there is 4% speed-up because of the large pages.
- For 2048 MB hash on 64-bit there is 8% speed-up.
Not really a big deal, but why not...
Robert
The dowload package that is available at http://www.cruxis.com/chess/houdini.htm contains these 2 changes:
- large page support (works both in 64-bit and 32-bit Windows)
- 32-bit version with support of up to 8 cores instead of 4
If you don't need large page support or 32-bit 8-cores version, there is no reason to download the new files. The new engines produce *exactly* the same output as the old.
For the large page support, there is a hidden command "lp" that will show you how much large page memory is available in different sizes.
Simply run the engine by double-clicking on the executable, then enter the command lp. This will produce for example the following output:
Code: Select all
Houdini 1.5 x64
(c) 2010 Robert Houdart
info string POPCNT available
info string 128 MB Large Page Hash
lp
=======================================================
Large page size 2 MB: 1382 allocated
Large page size 4 MB: 663 allocated
Large page size 8 MB: 325 allocated
Large page size 16 MB: 159 allocated
Large page size 32 MB: 77 allocated
Large page size 64 MB: 36 allocated
Large page size 128 MB: 17 allocated
Large page size 256 MB: 8 allocated
Large page size 512 MB: 4 allocated
Large page size 1024 MB: 2 allocated
Large page size 2048 MB: 1 allocated
Large page size 4096 MB: 0 allocated
=======================================================
setoption name hash value 2048
info string 2048 MB Large Page HashI've done some speed comparisons:
- For 512 MB hash on 32-bit there is 4% speed-up because of the large pages.
- For 2048 MB hash on 64-bit there is 8% speed-up.
Not really a big deal, but why not...
Robert