Alexander Dalloz wrote:
You mean not Severn, which was a Fedora beta, but you mean Taroon. I just checked that over the kernel version you give and that matches.
Oops. Indeed I meant Taroon. Too many nonsensical (to me) names...
4 times up to 20 times faster on Taroon compared to Fedora Core 1 is amazingly. Are you running one specific multithreaded application or a set of those? How do you measure the time it takes - by "time program"?
Yes, I've just been doing some basic profiling with 'time program' using one specific multithreaded (Java-based) application with various input files. To be more exact, I only see the differences on the largest of these sample cases, less intensive runs show a smaller difference.
FC1.3 runs... realtime: 2128s 2271s 7418s usertime: 693s 697s 748s
Taroon runs... realtime: 735s 765s usertime: 693s 728s
The RHEL kernel is very optimized for big machines with much RAM, multiprozessors and so on. Can you describe your machine park a little bit?
8 x dual 2.8 GHz Dell PowerEdge 1750 8 x dual 2.4 GHz Dell PowerEdge 2650 8 x dual 2.2 GHz Dell PowerEdge 2650 8 x dual 1.2GHz IBM eServers 12 x dual 1.2GHz Dell PowerEdge 2550
all systems have 2GB of RAM
The testing was done primarily using the 1750s, but I get comparable results from the 2650s. Most of the pool is still running RH7.3 and I'm trying to figure out the best upgrade path for them (these tests don't even run without NPTL).
Any informed suggestions from the community?Maybe you should post you question on the fedora-devel list. It seems the Redhat folks are paying there more attention to such questions than here.
Thanks. I'll probably want to write up a slightly more technically complete version for that venue. Here I'm mostly hoping for general kernel-analysis advice.
