Re: [boost] very poor thread performance

From: Lance.Diduck_at_[hidden]
Date: 2008-05-14 18:13:02

>Changing from using a std::vector<int> with a single space allocation
(not push_back) to a int[] improved the 
>speed but not scalability...
Now that you've fixed the measurement problem, give it a try with other
containers, and doing other operations. You will find some combination
that demonstrates that this does not always scale like you expect.
-----Original Message-----
From: boost-bounces_at_[hidden]
[mailto:boost-bounces_at_[hidden]] On Behalf Of James Sutherland
Sent: Wednesday, May 14, 2008 5:23 PM
To: boost_at_[hidden]
Subject: Re: [boost] very poor thread performance

>
> The result has been noticed before. In fact I wrote about it in 
> several posts on c.l.c++.m, and in N2486 in the first few pages it 
> uses this effect to illustrate a point about allocators.
> Nevertheless, the result is still surprising!!
> What is worse is that different compilers and libraries will give you 
> way different results for this test, so it is not just a function of 
> Intel. ( I have not tried to reproduce the results on anything but 
> intel).
>

Changing from using a std::vector<int> with a single space allocation
(not push_back) to a int[] improved the speed but not scalability...

James
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