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voffka wrote: ↑Fri Oct 11, 2019 8:56 pm 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?

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).

xr_a_y wrote: ↑Fri Oct 11, 2019 9:51 pm 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.

voffka wrote: ↑Wed Oct 16, 2019 5:29 pm xr_a_y ,

xr_a_y wrote: ↑Fri Oct 11, 2019 9:51 pm 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.

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

xr_a_y wrote: ↑Wed Oct 16, 2019 7:19 pm

voffka wrote: ↑Wed Oct 16, 2019 5:29 pm xr_a_y ,

xr_a_y wrote: ↑Fri Oct 11, 2019 9:51 pm 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.

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

Thanks for the advice, i'll run no-TT little tourney.

voffka wrote: ↑Sun Oct 20, 2019 7:44 pm 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.