Comment 17 for bug 1638695

Hello,

Following doko's advice, I ran a set of test with PGO & LTO optimization disabled.

Here are the results : https://docs.google.com/spreadsheets/d/1tTlEOvMypwKwi99XHjvuQFE14_jpBBLy0-Mk6bjkvL0/edit#gid=1169944329

This may bring more light to the investigation as it appear that with LTO & PGO optimisation disabled on Trusty, the trusty version becomes slower than the Xenial stock version. Disabling optimisation on Xenial makes little difference though.

So maybe the PGO & LTO optimisation on Trusty is more efficient than on Xenial and leads to better results,hence better performance. Just a thought