Bots and Simulations > Evolution and Internet Sharing Sims

cycles/sec

<< < (2/2)

jknilinux:
Nums: Wait, if it splits a single-threaded process across 2 cores, isn't that pretty much automatic parallelization? I thought multiple cores won't increase the speed of a single-threaded process...

Testlund: Great! So, assuming I have a 4-core processor, would DB run faster if I run 1 big sim or if I run 4 small sims and assign 1 to each core, and connect them with teleports?

Numsgil:

--- Quote from: Testlund ---It's quite remarkable that there are many new games/programs not optimised for more than 1 core, now when even dual-cores are getting old and you have quad-cores!

Software makers are starting to lack behind. It used to be the other way around. I have a few old game titles that it took several years before there were hardware that could run them smoothly.

Software and hardware makers should talk to each other more often.
--- End quote ---

The problem is that for many decades home PCs were single core machines, and that single core was getting exponentially faster.  Hardware makers have since hit a brick wall in single core speed, so they've begun branching out "horizontally" with more cores.  But programming for more cores requires more than one thread, and programming with multiple threads is hard because you can't always predict what one thread is doing during another thread's execution.  They might be trying to write to the same place in memory, and then they'll stomp on each other and you'll get impossible-to-track-down bugs.  So you need to use special commands to make sure that doesn't happen.  But if you use too many of those commands your program will actually run slower.


--- Quote from: jknilinux ---Nums: Wait, if it splits a single-threaded process across 2 cores, isn't that pretty much automatic parallelization? I thought multiple cores won't increase the speed of a single-threaded process...
--- End quote ---

It splits them across multiple cores to load balance.  But only one core is ever active at a single time.  So 50% of two cores is still only 1 core worth of processing power.


--- Quote ---Testlund: Great! So, assuming I have a 4-core processor, would DB run faster if I run 1 big sim or if I run 4 small sims and assign 1 to each core, and connect them with teleports?
--- End quote ---

4 smaller sims.

Testlund:
Here's an example of DB running on two cores connected with teleporters.

jknilinux:
Awesome! Thanks!

Navigation

[0] Message Index

[*] Previous page