VOGONS


First post, by ih8registrations

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Howdy ho,

Apply from root dosbox directory "patch -p0 < optimize.diff".

Optimizations to normal_loop, some pic routines, and a little touch up to the mixer handler. ie. speedup isn't cpu core specific.

Rearrangment for fallthrough to the most common paths and ridding of jumps mainly.

Timed with rdtsc and just used variables to track common paths.

Enjoy!

Oh yeah, speed up is relative to an athlon xp /w 256k l2, so something like an athlon 64 may not see as much an improvement since it handles thrashing better.

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Reply 2 of 10, by Qbix

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well my guess would be that most "speed" comes from the fact that you reduced the amount of gfx events.

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Reply 5 of 10, by avatar_58

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What game would benefit from 10% increases? 😕 Anything that is too "slow" would only cause sound stuttering really. Therefore you would need much more than 10%.

Reply 8 of 10, by DosFreak

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Speaking of speed increases....

I reinstalled 2003 Server today and benchmarked DosBox, Now I can use a few thousand more cycles in 2003 than I could on 2000. Hopefully it was some driver or software slowing down 2000 and not some difference between 2003/2000. I'll True Image my system and revert back and see if it's the same.

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Reply 9 of 10, by icemann

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Wonder what the cycle difference is between win98 and XP. I was using 98 right up until midway through last year and I haven`t noticed any difference really since the change.

Two stones, two crosses, the rest is just icing. - 7th Guest