On Thu, Nov 22, 2012 at 2:05 PM, Amit Kapila <amit.kap...@huawei.com> wrote:
> ** ** > > > ** ** > > >Sorry, I haven't followed this thread at all, but the numbers (43171 and > 57920) in the last two runs of @mv-free-list for 32 clients look > aberrations, no ? I wonder if *>*that's skewing the average.**** > > ** ** > > Yes, that is one of the main reasons, but in all runs this is consistent > that for 32 clients or above this kind of numbers are observed.**** > > Even Jeff has pointed the similar thing in one of his mails and suggested > to run the tests such that first test should run “with patch” and then > “without patch”. **** > > After doing what he suggested the observations are still similar.**** > > ** > Are we convinced that the jump that we are seeing is a real one then ? I'm a bit surprised because it happens only with the patch and only for 32 clients. How would you explain that ? > ** > > ** ** > > > I also looked at the the Results.htm file down thread. There seem to be > a steep degradation when the shared buffers are increased from 5GB to 10GB, > both with and **** > > > without the patch. Is that expected ? If so, isn't that worth > investigating and possibly even fixing before we do anything else ?**** > > ** ** > > The reason for decrease in performance is that when shared buffers are > increased from 5GB to 10GB, the I/O starts as after increasing it cannot > hold all**** > > the data in OS buffers. > Shouldn't that data be in the shared buffers if not the OS cache and hence approximately same IO will be required ? Again, the drop in the performance is so severe that it seems worth investigating that further, especially because you can reproduce it reliably. Thanks, Pavan
