Timeline for OpenGL : sluggish performance in extracting texture from GPU
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Mar 7, 2013 at 11:17 | vote | accept | Cyan | ||
| Dec 18, 2012 at 23:56 | comment | added | Cyan | Follow up : my dev station was just updated, from WinXP-32 to Win7-64 (corporate managed). I immediately tried the PBOTest application above. The results are radically changed : now texture transfer is down to 0.4ms, while it was 20ms previously. It's a 50x increase. Both drivers were up to date, but apparently, only Win7 ones were properly optimised. It's also interesting to note that, in both cases, PBO or not PBO, it made no difference at all. | |
| Dec 2, 2012 at 0:11 | comment | added | Cyan | Well, i may be out of luck. The website you recommend to read (and which is indeed very good) also has a test program to demonstrate and measure the effect of PBO. On my test system, turning PBO on or off doesn't change anything. Same speed. And btw, the speed is confirmed as being miserable, at just 1.2MPixels/s. That's well below my expectation. | |
| Dec 2, 2012 at 0:00 | comment | added | Nathan Reed | @Cyan If you want to properly benchmark GPU operations (as opposed to CPU calls that queue up GPU operations), you should look into ARB_timer_query. | |
| Dec 1, 2012 at 23:40 | comment | added | Cyan | Wow, i initially thought that i was already doing that, but then, looking at the documentation you point at, it seems quite much more complex. Note also that the way performance is being benchmarked is not exactly friendly with this methodology. But well, let's have a look at it anyway. | |
| Dec 1, 2012 at 18:06 | history | answered | Nathan Reed | CC BY-SA 3.0 |