Re: Thread-safety issues in QtHandles

[Michael Goffioul]

On Tue, Nov 15, 2011 at 10:12 AM, Michael Goffioul
<address@hidden> wrote:
> On Tue, Nov 15, 2011 at 9:53 AM, Søren Hauberg <address@hidden> wrote:
>> I just tried this on 32-bit Linux, and it works even though I see a
>> noticeable slow-down. I tried running
>>
>>  clear; tic, N = 1000; for a = 1:N, for b = 1:N, A (a, b) = a; endfor,
>> endfor; toc
>>
>> in Octave with thread-safety enabled and got a run-time of 12.3 seconds
>> and without it drops to 8.8 seconds.
>
> This is indeed a large slow-down, I'll test it on my platform as well,
> for comparison.

For comparison, on my Linux platform, Intel E5300 2.6GHz 2GB RAM, I
ran the test above with the patch applied (on
http://hg.savannah.gnu.org/hgweb/octave/rev/69afe121f07e), once with
--enable-atomic-refcount, once with --disable-atomic-refcount, octave
compiled with "-g -O2", the execution time is as follows:
- ./configure --enable-atomic-refcount: ~13s
- ./configure --disable-atomic-refcount: ~10.7s

So there is a slowdown, but not as large as the one you have.

Michael.