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Re: cross gcc-4.1.2-12 packages

On 23/06/2007, at 2:52 PM, Brian Morris wrote:

I have plan to get a comm slot e/net card and then my q630 could
take two cards (although the lcIII card in there now is need by q605),
when my budget allows. then I could test using two network cards to
increase the network speed. but yes that is not the bottleneck (or
limiting factor).


Does it already have 128+ ram? Get the ram first.

The speed of disk write for paging memory is significantly slower than network.

Because of the way distcc and make waits to finish a directory a slow machine plodding along drags the rest of the machines with it.

Having done some ifconfig volume and timing testing I found the biggest slowdown was when a machine hit the upper limit of RAM and started paging. The next was when the CPU of the host started to page out on threads.

The testing went from 8500 (Just installing an additional card) to 13000 with an additional NIC (specific routing used). but to 17500 with an additional NIC and tuned setup.

I suggest you get some code, make clean the "time make -j?" and work out the fastest combination.
My figures are j+2 for 36mb and j+8 for 128Mb machines.

How you set up your /etc/distcc/hosts is also important. Just doing will limit all machines to 2 threads(because of the round- robin approach of distcc). Not limiting will cause page out on low- mem machines. I've found virtual interfaces to take extra lots of j2-3 work well., and are the same machine with virtual interfaces, the 9 is because the server obviously polls the number of cc threads (there are a lot of Blocked messages on distcc-mon with
Michael Tomkins
+61 (0) 408 172 142

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