[OpenJDK 2D-Dev] [9] Review Request: 8041129 [OGL] surface->sw blit is extremely slow

[Jim Graham]

Some of the other calls are followed by resetting it to 0, but not all 
(notably in that same file line 335 sets it to a potentially non-zero 
value and does not reset it).

Actually, I just noticed that this one is using PACK_SKIP, but the other 
cases are using UNPACK_SKIP.  Still, between the two attributes, there 
is inconsistency on whether or not the code expects an operation to 
reset the values, or must set them all up before each operation...

			...jim

On 4/21/14 7:52 AM, Andrew Brygin wrote:
> Hello Sergey,
>
>   the fast path skips j2d_glPixelStorei(GL_PACK_SKIP_ROWS, dsty).
>
>   Could you please clarify why? I think that initial value of dsty
>   (dstInfo.bounds.y1) can be non-zero, and this operation
>   seem to be required...
>
> Thanks,
> Andrew
>
> On 4/21/2014 6:17 PM, Sergey Bylokhov wrote:
>> Hello.
>> Please review the fix for jdk 9.
>> This issue initially was found in FX[1], and there is description of
>> this problem.
>> In the fix the flip operation is done using memcpy after the whole
>> image was moved from gpu to cpu.
>>
>> [1] https://javafx-jira.kenai.com/browse/RT-30035
>> Bug: https://bugs.openjdk.java.net/browse/JDK-8041129
>> Webrev can be found at:
>> http://cr.openjdk.java.net/~serb/8041129/webrev.01
>>
>> Benchmarks:
>> ==========================================================
>> Windows 7 x64, lenovo T410, nvidia NVS 3100M
>> http://cr.openjdk.java.net/~serb/8041129/J2DBench/results
>> base ogl vs base d3d vs fixed ogl
>> Summary:
>>   OGL-base-nvidia-windows:
>>     Number of tests:  10
>>     Overall average:  2239.9261323744704
>>     Best spread:      1.72% variance
>>     Worst spread:     88.61% variance
>>     (Basis for results comparison)
>>
>>   OGL-fix-nvidia-windows:
>>     Number of tests:  10
>>     Overall average:  166667.93024226945
>>     Best spread:      1.23% variance
>>     Worst spread:     66.19% variance
>>     Comparison to basis:
>>       Best result:      13719.74% of basis
>>       Worst result:     97.17% of basis
>>       Number of wins:   8
>>       Number of ties:   1
>>       Number of losses: 1
>>
>>   D3D-base-nvidia-windows:
>>     Number of tests:  10
>>     Overall average:  29755.21747098
>>     Best spread:      0.34% variance
>>     Worst spread:     61.12% variance
>>     Comparison to basis:
>>       Best result:      12068.41% of basis
>>       Worst result:     8.05% of basis
>>       Number of wins:   6
>>       Number of ties:   0
>>       Number of losses: 4
>>
>> ==========================================================
>> OSX 10.8.5, macbook pro retina, nvidia GeForce GT 650M 1024 MB
>> http://cr.openjdk.java.net/~serb/8041129/J2DBench-osx/results-nvidia-osx.txt
>>
>> Summary:
>>   OGL-base-nvidia-osx:
>>     Number of tests:  10
>>     Overall average:  710.7070782394075
>>     Best spread:      0.73% variance
>>     Worst spread:     5.72% variance
>>     (Basis for results comparison)
>>
>>   OGL-fix-nvidia-osx:
>>     Number of tests:  10
>>     Overall average:  11032.674771293528
>>     Best spread:      0.62% variance
>>     Worst spread:     8.14% variance
>>     Comparison to basis:
>>       Best result:      4659.95% of basis
>>       Worst result:     169.66% of basis
>>       Number of wins:   10
>>       Number of ties:   0
>>       Number of losses: 0
>>
>> ==========================================================
>> OSX 10.8.5, macbook pro retina, Intel HD Graphics 4000
>> http://cr.openjdk.java.net/~serb/8041129/J2DBench-osx/results-intel-osx.txt
>>
>> Summary:
>>   OGL-base-intel-osx:
>>     Number of tests:  10
>>     Overall average:  3993.5366388495613
>>     Best spread:      0.65% variance
>>     Worst spread:     20.91% variance
>>     (Basis for results comparison)
>>
>>   OGL-fix-intel-osx:
>>     Number of tests:  10
>>     Overall average:  10197.361705976433
>>     Best spread:      0.72% variance
>>     Worst spread:     38.4% variance
>>     Comparison to basis:
>>       Best result:      491.0% of basis
>>       Worst result:     108.61% of basis
>>       Number of wins:   10
>>       Number of ties:   0
>>       Number of losses: 0
>>
>> Thanks to Anton for the initial version of the fix.
>>
>