|Message: Re: Surprisingly poor performance of Geant4.9.2.p01 on a bi-quad-core Intel xeon machine||Not Logged In (login)|
Click on the Forum title, e.g. on the "Forums by Category" page, to read a sequence of postings to the Forum and its threads all in one page. If you are only interested in one thread or the thread following a specific posting, click the thread or the posting, which takes you to a smaller page, which contains only the part you are interested in and may be easier to navigate.
Messages are "chained" if there are only replies at the first level, i.e. 1/1.html, 1/1/1.html etc. In case of "chained" messages the message number is replaced by the icon and there is no indentation.
Inline: Display the subject line only or also the text of the posting(s); for the choice "All" the "Outline" choices are switched off.
|1||0||1||no text / full text of posting|
|2||1||All||text for level 1 only / text for All postings|
Outline: Choose the depth of the posting thread, successive toggle controls provide increasing detail.
|1||2||1||2 levels / 1 level (original posting)|
|2||3||2||3 levels / 2 levels|
|3||3||All||3 levels / all levels (all postings)|
> Hello, > > You have made it clear that the newer system was using a 64bit > operating system and that the older system was using a 32bit operating > system. 32bit executables can be faster than 64bit > executables. However, you did not provide enough evidence to > conclusively deduce that the wordlength accounts for your observations > because: > * you have not made it clear that both sets of measurements were for > Geant4.9.2.p01; > * the Linux kernels do not differ merely by wordlength: they are > 2.6.30-gentoo-r4 and 2.6.24-gentoo-r8; > and > * other potentially influential factors have been left unreported, > such as the compilers used; and the Geant configuration options used > when compiling and installing Geant. > > Yours sincerely, > Nicholas Paul Colin Gloster >
The compiler used is gcc-4.1.2 in both machines. The same configuration option from Linux-g++ were used. For the quad-core machine I also tried to change the compiler ( gcc-3.4.6, 4.1.2 and 4.3.3) and options (like -mtune=native -msse4.1), but the results are almost the same.
I also tried to compile my Geant4 application by using mpicxx and then ran the executable with a single thread, but nothing gets better.
|Inline Depth:||Outline Depth:||Add message:|