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| -rw-r--r-- | docbook/results-2.docbook | 538 | ||||
| -rw-r--r-- | tests/configure.ac | 2 |
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diff --git a/docbook/results-2.docbook b/docbook/results-2.docbook new file mode 100644 index 0000000..cdd9aca --- /dev/null +++ b/docbook/results-2.docbook @@ -0,0 +1,538 @@ +<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> + +<article id="fullscreen2" lang="en"> + <articleinfo> + <title>Fullscreen 2 ( DRAFT I )</title> + <author> + <firstname>Matthew</firstname> + <surname>Allum</surname> + <affiliation> + <orgname>Opened Hand Ltd</orgname> + </affiliation> + <email>mallum@openedhand.com</email> + </author> + + <copyright> + <year>2005</year> + <holder>OpenedHand Ltd</holder> + </copyright> + </articleinfo> + +<section><title>Introduction</title> +<para> + +This report builds on the original fullscreen blit benchmark tests on +handheld ARM based devices. The focus is moved to font glyph rendering +speeds via different mechanisms, image blitting via GDK and the +original tests on a newer 2.6 kernel. + +</para> + +<para> + +Graphics output is assumed to be by means of writing data to a 'dumb' kernel +framebuffer device via direct means or an XServer. + +</para> + +</section> + +<section><title>Tests</title> +<para> + +For the tests simple test programs were created. They are +written in C. the initial tests written are as follows. + +</para> +<para> + +As well as the original tests, the following new tests have been created; + +</para> + +<para> + +<variablelist> + +<varlistentry> +<term>test-gdk</term> +<listitem> + +<para> + +Performs blits via GDK-pixbufs on X. Blits are performed to a GTK +drawing area widget with double buffering turned off. This makes the +test comparible to the others as they perform no double buffering. + +</para> + +</listitem> +</varlistentry> + +<varlistentry> +<term>test-freetype</term> +<listitem> +<para> + +Renders to lines of glyphs to the framebuffer using the freetype library. + +</para> + +</listitem> +</varlistentry> + +<varlistentry> +<term>test-xft</term> +<listitem> + +<para> + +Renders lines of glyphs to an X window using the Xft2 extension. + +</para> + +</listitem> +</varlistentry> + +<varlistentry> +<term>test-pango</term> +<listitem> +<para> + +Renders lines of glyphs to an X window using the Pango-Xft library. +No pango layout or GTK functionality is used. + +</para> + +</listitem> +</varlistentry> + +<varlistentry> +<term>test-pango-layout</term> +<listitem> +<para> + +Renders lines of glyphs to a GTK drawing area ( with double buffering +disabled ) via Pango layouts. GTK/GDK must be used as only versions of +pango < 1.8 expose layout functionality to 'raw xft'. + +</para> + +</listitem> +</varlistentry> + +</variablelist> + +</para> + +<para> + +Note all font based tests take similar arguments to specify what text +is rendered ( run tests with -h to see ). By default Vera Sans fonts +is used at 18 points with 20 lines of the ascii alphabet ( a -> z) +being rendered 200 times. + +</para> + +</section> +<section><title>Test Platforms</title> + +<para> +The tests were run on the following platforms; +</para> + +<variablelist> + +<varlistentry> + <term>Sharp Zaurus c760 ( Husky )</term> + <listitem> + <para> + <itemizedlist mark="bullet" spacing="compact"> + <listitem> + <para>CPU: XScale-PXA255 rev 6</para> + </listitem> + <listitem> + <para>RAM: 64MB</para> + </listitem> + <listitem> + <para>Display: 640x480x16 LCD</para> + </listitem> + <listitem> + <para>GFX Chip: ATI IMAGEON W100</para> + </listitem> + <listitem> + <para>X11: Freedesktop.org kdrive Xfbdev server</para> + </listitem> + <listitem> + <para>kernel: 2.6.11-rc2-openzaurus ( softfloat )</para> + </listitem> + </itemizedlist> + </para> + </listitem> +</varlistentry> + + +<varlistentry> +<term>Ipaq 5500</term> +<listitem> +<para> +<itemizedlist mark="bullet" spacing="compact"> +<listitem> +<para>CPU: XScale-PXA255 rev 6 </para> +</listitem> +<listitem> +<para>RAM: 128MB</para> +</listitem> +<listitem> +<para>Display: 320x240x16 LCD</para> +</listitem> +<listitem> +<para>GFX Chip: MediaQ</para> +</listitem> +<listitem> +<para>X11: Freedesktop.org kdrive Xfbdev server</para> +</listitem> +<listitem> +<para>kernel: 2.4.19-rmk6-pxa1-hh37</para> +</listitem> +</itemizedlist> +</para> +</listitem> +</varlistentry> + + +<varlistentry> +<term>Ipaq 3850</term> +<listitem> +<para> +<itemizedlist mark="bullet" spacing="compact"> +<listitem> +<para>CPU: StrongARM-1110 rev 9 </para> +</listitem> +<listitem> +<para>RAM: 128MB</para> +</listitem> +<listitem> +<para>Display: 320x240x16 LCD</para> +</listitem> +<listitem> +<para>GFX Chip: None</para> +</listitem> +<listitem> +<para>X11: Freedesktop.org kdrive Xfbdev server</para> +</listitem> +<listitem> +<para>kernel: 2.4.19-rmk6-pxa1-hh37</para> +</listitem> +</itemizedlist> +</para> +</listitem> +</varlistentry> + +</variablelist> + + +</section> +<section> +<title>Platform Notes</title> + +<para> + +All machines have the same version XServer and X librarys. Both of +which are from recent checkouts of the freedesktop.org cvs kdrive +source. In all of the above cases no hardware acceleration was +used. The display is also running in its 'natural' orientation. + +</para> + +<para> + +The c760 device is very similar hardware wise to that of the c700, +except having a larger battery and increased internal flash +storage. The binaries built on the c760 are built using the softfloat +floating point emulation provided by newer gcc's. This is reportadly +supposedly much better performing than kernel 'hardfloat' floating +point performance. + +</para> + +</section> + +<section><title>Benchmark Results</title> + +<section><title>Zaurus c760</title> + +<para> + +<literallayout class="monospaced"> + +test-fb: Framebuffer write speed: 12177 KB/Sec + +test-x: X-SHM write speed: 11015 KB/sec + +test-gdk: write speed: 6163 KB/sec + +test-freetype: Total time 44971 ms, 52000 glyphs rendered = approx 1156 glyphs per second + +test-xft: Total time 5540 ms, 52000 glyphs rendered = approx 9386 glyphs per second + +test-pango: Total time 7747 ms, 52000 glyphs rendered = approx 6712 glyphs per second + +test-pango-layout: Total time 9357 ms, 52000 glyphs rendered = approx 5557 glyphs per second + + + + +</literallayout> + +</para> + +</section> + +<section><title>ipaq 5500</title> + +<para> + +<literallayout class="monospaced"> + +test-fb: Framebuffer write speed: 7425 KB/Sec + +test-x: Approx frame rate: 42 frames/sec + +test-gdk: write speed: 5184 KB/sec + +test-freetype: Total time 30386 ms, 52000 glyphs rendered = approx 1711 glyphs ++per second + +test-xft: Total time 2738 ms, 52000 glyphs rendered = approx 18991 glyphs per ++second + +test-pango: Total time 4265 ms, 52000 glyphs rendered = approx 12192 +glyphs per second + +test-pango-layout: Total time 5565 ms, 52000 glyphs rendered = approx +9344 glyphs per second + +</literallayout> + +</para> + +</section> + +<section><title>ipaq 3850</title> + +<para> + +<literallayout class="monospaced"> + +test-x: X-SHM write speed: 23547 KB/sec + +test-gdk: write speed: 11144 KB/sec + +test-freetype: Total time 54325 ms, 52000 glyphs rendered = approx 957 glyphs per second + +test-xft: Total time 2899 ms, 52000 glyphs rendered = approx 17937 glyphs per second + +test-pango-layout: Total time 5602 ms, 52000 glyphs rendered = approx 9282 glyphs per second + +test-pango: Total time 4538 ms, 52000 glyphs rendered = approx 11458 glyphs per second + + + +</literallayout> + +</para> + +</section> + +</section> + +<section><title>Discussion</title> + +<section><title>Blitting</title> + +<para> + +We see no marked improvements on blit speeds since previous tests with +results much the same. This is to be expected though as no major +developments have happened in this area since the tests were last run. + +</para> +<para> + +However the c760 is using a 2.6 kernel and performance has actually +degraded. This is not too much of a worry though, the 2.6 kernel on +the c760 is very immature and the performance degration has been +reported to the fb driver author. The fb driver is infact a rewrite of +the 2.4 driver without access to the display chip technical details. + +</para> +<para> + +The 5500 framebuffer access is also very slow. The fb driver lacks +acceleration functionality provided by the mediaq chip and it seems +with display driver cheap in place just slows down the general case - +The 3800 is faster. + +</para> +<para> + +GDK pixbuf blits take a further speed hit over pur shm. A reason for +this could be the pixbuf internals having the extra work of rounding +down from 24bpp RGB to 16bpp RGB before blitting to the server. + +</para> + +<para> + +Interstingly this difference is not as large when run on an x86 +system. On a 16bpp Xephyr I get 25917 KB/sec ( gtk ) vs 28195 KB/sec +( x ). Could there perhaps be a more serious issue with gtk on ARM ? +This needs further investigation. + +</para> + +<para> + +The gtk test disabled the internal double buffering on the drawing +area widget. Performing such a test without double buffering requires +putting the paint in an idle handler. Such a test was created ( +test-gdk-idle ) and the results were just slightly worse with; + +</para> +<para> + +<literallayout class="monospaced"> + + ./test-gdk-idle +test-gdk-idle: write speed: 11227 KB/sec + +</literallayout> + +</para> +<para> + +In GTK double buffering means that when expose() is called for a +widget, its window is replaced with a off-screen drawable, and then on +returning from the expose() the offscreen drawable is blitted onscreen +and its window restored. Thus any performance loss is likely due to +the frequency of the idle handler getting called. ( assuming the cost +is moving the pixmap from off -> on screen is made up by blitting off +screen ). + +</para> + +</section> + +<section><title>Glyphs</title> + +<para> + +In all cases the xft rendering is fastest. The plain pango line +rendering is approximatly 30% slower, with pango layout rendering +being approxinmatly a further 10-20% slower. + +</para> + +<para> + +The freetype test is much slower than expected on ARM platforms. On a +desktop x86 system the results are much improved with speeds as +expected greater than that of xft. The reason for the low performance +on arm is likely the lack of any glyph bitmap caching per glyph render +and the bitmap generation using much floating point. + +</para> +<para> + +This proves that xft is caching glyph bitmap generation and it is definetly +required for acceptable performance. + +</para> +<para> + +To further improve on this a version of test-freetype ( +test-freetype-cached.c ) was created that pregenerated glypth bitmaps +in a simple cache before painting them. Running on the 3800 gave; + +</para> +<para> + +<literallayout class="monospaced"> + +test-freetype-cached: pre generated glyphs in 1159 ms +test-freetype-cached: Total time 2055 ms, + 52000 glyphs rendered = approx 25304 glyphs per second + +</literallayout> + +</para> +<para> + +It should also be noted that the test-freetype test very crudely +renders just the 8 bit mask to the display ( all bits > 0 are blitted ). + +</para> + +<para> + +test-pango writes text via the low level pango xft calls to render +lines of text to an X window. No gdk/gtk calls are used. To +investigate the overhead of rendering to a gtk widget and window two +further tests were created - test-pango-gdk to a GDk Window and +test_pango_gtk - to GTK drawing area. Benchmarks from these were +approximatly equal. Another test was created using gdk_draw_glyphs() +instead of pango_xft_render() again results were comparable - +indicating draw_glyphs is just a wrapper around pango_xft_render(). + +</para> + +<para> + +test-pango-layout uses the pango layout api to render onto a gtk +drawing area - most GTK widgets use layouts. There is an overhead +involved, this could be worse it we were rendering more than just a +simple line. + +</para> + + +</section> + +</section> + +<section><title>Improvements and Future Directions</title> + +<para> + +Some ideas for future tests. + +</para> +<para> + +<itemizedlist mark="bullet" spacing="compact"> +<listitem> +<para>Investigate gtk slow blits more fully.</para> +</listitem> + +</itemizedlist> + +</para> + +</section> + +<section><title>References</title> +<para> + +<itemizedlist mark="bullet" spacing="compact"> +<listitem> +<para><ulink url="sources/">Test Source Code</ulink></para> +</listitem> +</itemizedlist> + +</para> + +</section> + +</article> + diff --git a/tests/configure.ac b/tests/configure.ac index 1019804..77452da 100644 --- a/tests/configure.ac +++ b/tests/configure.ac @@ -1,5 +1,5 @@ AC_PREREQ(2.53) -AC_INIT([fstests], 0.0, [mallum@o-hand.com]) +AC_INIT([fstests], 0.1, [mallum@o-hand.com]) AC_CONFIG_SRCDIR([test-x.c]) AM_INIT_AUTOMAKE() |