>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.
