09054: tokio and clones: performance regression

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
09054	Speed	Minor	Always	21 days ago	21 days ago

Tester	Augusto	View Status	Public	Platform	MAME (Unofficial Binary)
Assigned To	hap	Resolution	Fixed	OS	Linux (64-bit)
Status [?]	Resolved			Driver	taito/bublbobl.cpp
Version	0.271	Fixed in Version	0.274GIT	Build	64-bit
		Fixed in Git Commit	01e1be2	Github Pull Request #

Summary	09054: tokio and clones: performance regression
Description	Hello. Thanks for reading my topic. MAME is accuracy and precision and so will be used more CPU, but is as if that game not is related with it. The game Tokio are having much slowdown as never had before in MAME recent versions. Reading mameinfo.dat the last change in driver was in 0.191 not having slowdown. OS Linux kernel 6.8 Ubuntu 24.04 and CPU used is AMD FX 6 cores 3500 MHz enough for several games from 80's. In MAME current versions that game run in 72 % speed if CPU is using power profile energy saver and 185 % speed if using power profile high performance. In comparison other game using the same driver is Bubble Bobble and run in 220 % speed if CPU is using power profile energy saver and 580 % speed if using power profile high performance. Tokio use 2x Z80 6 MHz , 1 Z80 3 MHz and 1 MC68705P5 3 MHz and only YM2203. Not netlist in sound. That arcade use simple graphics and now the cpu requiriment is compared with other games with much better hardware. In MAME recent versions was done changes in Z80 core, but that changes not has done slowdowns in several others games using Z80 and Tokio not is affected because if debugging in OSD slider and overclocking all CPUs to 200 % the performance are from 72 % speed to 48 % and 185 % to 121 % speed. That game has moments run in slowdown being strange because others games using multiple Z80 run with high speed for example xevious is 680 % speed and in same cpu run seattle driver in 85 % speed. I not remember when that performance regression has happened. I had played that game in 12-2023 and not had that slowdown. Have something wrong affecting the performance of that game. Tokio is simple to demand high cpu usage. I see happening similar issue only with others games using 2 drivers : cedar_magnet and seibuspi. Have an good week and new happy year.
Steps To Reproduce
Additional Information
Github Commit

Flags
Regression Version
Affected Sets / Systems	tokio and clones

Attached Files

No.22719 hap Developer 21 days ago	I'm not sure I'd say this is a bug, more like an expectation after the Z80 rewrite. Z80 emulation timing itself has become more accurate and slower. And doing perfect synchronization with multiple CPUs, Z80 is slower since the minimum number of cycles per timeslice is much less than before. Anyway, I'm going to test the game with 6000hz quantum (the value from bublbobl), see if I run into any issues.
No.22720 Augusto Tester 21 days ago	You are correct about Z80 changes. However as I had posted above even overclocking all CPUs to 200 % not does an much slowdown. I has tested several games using Z80 and the performance was exactly the same comparing with recent Z80 changes.
No.22721 hap Developer 21 days ago	I don't think MAME updates perfect interleave if you overclock a CPU with -cheat
No.22722 Augusto Tester 21 days ago	For me with my little knownledge if Z80 changes is use more cpu now doing an overclock test will to do an high slowdown , but not slowdown happen. I only see that same performance issue with more other 2 games.
No.22728 Augusto Tester 21 days ago	Thanks for doing an fix !!!! =)