Vivien,
Have you considered that the problem with long TC is not related to hash usage but rather to prunning conditions that are triggered differently in longer controls?
Looking for TT policy advice
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Re: Looking for TT policy advice
I cannot really answer yes to that question ... It may indeed be the case. Are you thinking of a particular parameter ?
I thought TT was a good candidate because with the used replacement scheme.
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Re: Looking for TT policy advice
Why would you want to store the score part? A hash move should always be searched first. An age field would be useless on an always-replace (or an under-cut) slot. And two bits would probably be large enough for it, so it could be easily packed with the bound-type flag, (whick also only needs 2 bits).
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Re: Looking for TT policy advice
You are right, I was too lazy and use the main move packing also inside TT. Test in progress now with a smaller entry size.hgm wrote: ↑Sat Oct 12, 2019 12:36 am Why would you want to store the score part? A hash move should always be searched first. An age field would be useless on an always-replace (or an under-cut) slot. And two bits would probably be large enough for it, so it could be easily packed with the bound-type flag, (whick also only needs 2 bits).
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Re: Looking for TT policy advice
xr_a_y ,
My intiution tells me that after you run the preliminary tests you will discover that hash usage is not a culprit. When I solved that Igel problem at short time control, it was an eval problem related to stupid me doing popcount on an uninitialized variable
I think instead of spending significant time on some idea it may be worth rechecking it: if you think Topple and Igel are better in longer tc and the suspect is use of hash, re-compile them both without hash (and some other engines) and run tests in faster time control without hash (Minic, Topple, Igel, some other engines?): this will at least give you a hint if you are going a right direction.
My intiution tells me that after you run the preliminary tests you will discover that hash usage is not a culprit. When I solved that Igel problem at short time control, it was an eval problem related to stupid me doing popcount on an uninitialized variable
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Re: Looking for TT policy advice
Thanks for the advice, i'll run no-TT little tourney.voffka wrote: ↑Wed Oct 16, 2019 5:29 pm xr_a_y ,
I think instead of spending significant time on some idea it may be worth rechecking it: if you think Topple and Igel are better in longer tc and the suspect is use of hash, re-compile them both without hash (and some other engines) and run tests in faster time control without hash (Minic, Topple, Igel, some other engines?): this will at least give you a hint if you are going a right direction.
My intiution tells me that after you run the preliminary tests you will discover that hash usage is not a culprit. When I solved that Igel problem at short time control, it was an eval problem related to stupid me doing popcount on an uninitialized variable
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Re: Looking for TT policy advice
So a first test, with only 1Mb TT for everybody gave very poor results for Minic (at least -150elo very others usually at same level). So not having a big enough TT is very bad for Minic. I'll check without TT code next.xr_a_y wrote: ↑Wed Oct 16, 2019 7:19 pmThanks for the advice, i'll run no-TT little tourney.voffka wrote: ↑Wed Oct 16, 2019 5:29 pm xr_a_y ,
I think instead of spending significant time on some idea it may be worth rechecking it: if you think Topple and Igel are better in longer tc and the suspect is use of hash, re-compile them both without hash (and some other engines) and run tests in faster time control without hash (Minic, Topple, Igel, some other engines?): this will at least give you a hint if you are going a right direction.
My intiution tells me that after you run the preliminary tests you will discover that hash usage is not a culprit. When I solved that Igel problem at short time control, it was an eval problem related to stupid me doing popcount on an uninitialized variable
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Re: Looking for TT policy advice
150 elo diff sounds like an engine playing without any TT at all. I remember measuring the impact of tt in Igel since I completely re-written it since the fork from Greko.
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Re: Looking for TT policy advice
Everybody had a 1Mb TT during this test. So there are two possibilities :
- either Minic TT policy is stupid for small TT
- or Minic has a serious bug that is mostly hidden by big TT