Opened 9 years ago

Closed 9 years ago

#152 closed task (fixed)

Apply performance options

Reported by: rudi Owned by:
Priority: minor Milestone: Qt 4.6.2
Component: General Version: 4.5.1 GA
Severity: low Keywords:
Cc:

Description

Since we need to use any piece of performance we can get and we don't have to support i386 CPUs, I suggest to let qmake generate the compiler options (for GCC4.x):

-march=i486 -mtune=generic

Don't expect wonders from that, but a small speed gain can be measured. The down side is, that the created code grows a bit in size.

Change History (6)

comment:1 Changed 9 years ago by dmik

This needs to be tested using the BLIT test (see the test result table in #101). Once I get numbers and these numbers demonstrate a noticeable performance boost, I will enable it.

comment:2 Changed 9 years ago by diver

speed w/o the above options:

driver/mode NO_DIVEDIVE=BLITDIVE=FBDIVE=FBSWM
Panorama/32bit (16M) 30258 41744 47460 44459

speed with the above options:

driver/mode NO_DIVEDIVE=BLITDIVE=FBDIVE=FBSWM
Panorama/32bit (16M) 31032 43670 48940 47789

comment:3 Changed 9 years ago by dmik

Not that bad. (The FBSWM test is probably not in the line because it depends on where your mouse is and how intensively you move it). I think it's worth doing it. I don't think there is anybody running an i386 PC and wanting to use Qt4.

comment:4 Changed 9 years ago by diver

  • Milestone changed from Qt Enhanced to Qt 4.6.2

i agree with the above and moved the ticket to 4.6.2 milestone.

comment:5 Changed 9 years ago by dmik

Done in r720.

comment:6 Changed 9 years ago by dmik

  • Resolution set to fixed
  • Status changed from new to closed
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