IDE support?

Brendan Eich brendan at
Tue Sep 13 15:54:43 PDT 2011

On Sep 13, 2011, at 3:49 PM, Bill Frantz wrote:

> I am always amused by the continuing demands for more performance. The only real advantage of performance as a major metric is that it is relatively easy to measure.
> If performance is your number one goal, then the only languages you should consider are assembler and machine language. :-)
> On the other hand, if you like safety, security, maintainability, understandability etc., then recognize that these features have associated costs.

I agree, of course. Still, it's surprising that JS, which is quite fast, is still considered the performance bottleneck. Profiles I see, ignoring JS-heavy benchmarks that don't match much real-world code, show we have work cut out elsewhere: DOM, layout, rendering...

Sure, putting game logic and physics engine in JS will hurt. Indeed we should be using the short-vector units and massively parallel GPUs (safely) from JS. More on this very soon.

> On 9/13/11 at 7:48, brendan at (Brendan Eich) wrote:
>> On Sep 13, 2011, at 5:33 AM, Andreas Rossberg wrote:
>>> * A big problem is predictability, it is a black art to get the best
>>> performance out of contemporary JS VMs.
>> This is the big one in my book. Optimization faults happen. But can we iterate till flat?
> A set of rules a developer interested in performance can use would be helpful. Particularly if they applied to more than one implementation. :-)

That will require iteration too, just to get VMs into alignment (assuming their maintainers are willing to do the work, which may mean converging on optimization hierarchy).

>>> * The massive complexity that comes with implementing all this affects
>>> stability.
>> This one I'm less sympathetic to, since we won't get rid of untyped JS up front. A sunk cost fallacy? If we could make a "clean break" (ahem), sure. Otherwise this cost must be paid.
> We could get better stability with simpler, less performant VMs. Some users might prefer the increased stability and security such a VM would offer.

Not in the large in today's browser market. A niche market, perhaps. Very niche.


More information about the es-discuss mailing list