The C/C++ is just faster. You can tune it. You know what is happening.
Also very important thing with C is that you can have a clear control how much of resources your program uses. And the most important resource is memory.
I don't know how relevant this is to computational finance, but in scientific computing you can use up an arbitrary amount of RAM in dimensionality-cursed fields. For instance, in neutron transport theory, the governing equation is in 7 continuous variables (or 6 in steady state), so that if you want your mesh to be twice as fine, your memory usage increases by 2^7 (or 2^6).
And, just so we're clear, that's multiplicative, not additive. So you're using 2^7 times as much memory as you were using before.
So memory costs grow linearly. Does your memory usage? If not, then any linear reduction of memory usage gained by switching languages can be very significant. It can also be the difference between being able to run a job on your 64GB machines, or needing to petition for more. Memory only increases at $7/GB so long as you can fit it into the rest of your hardware.
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The C/C++ is just faster. You can tune it. You know what is happening. Also very important thing with C is that you can have a clear control how much of resources your program uses. And the most important resource is memory.
Memory? Really? At ~$7 per Gigabyte of RAM I doubt that.
I don't know how relevant this is to computational finance, but in scientific computing you can use up an arbitrary amount of RAM in dimensionality-cursed fields. For instance, in neutron transport theory, the governing equation is in 7 continuous variables (or 6 in steady state), so that if you want your mesh to be twice as fine, your memory usage increases by 2^7 (or 2^6).
And, just so we're clear, that's multiplicative, not additive. So you're using 2^7 times as much memory as you were using before.
So memory costs grow linearly. Does your memory usage? If not, then any linear reduction of memory usage gained by switching languages can be very significant. It can also be the difference between being able to run a job on your 64GB machines, or needing to petition for more. Memory only increases at $7/GB so long as you can fit it into the rest of your hardware.
I think he was specifically referring to cache. You still take a large performance hit to have to go to main memory, and iirc nehalem has 12MB cache.