It is the second time I’m at foss.in and this time I was talking about the current work I’m doing on QtWebKit. Nokia is kind enough to give me enough time to explore the performance of QtWebKit (mostly on Qt Embedded Linux and ARM) and do fixes across the stack in WebKit, Qt or whereever we think it will be necessary. Performance for me comes in memory footprint and runtime speed (how long does it take?) and for this I…
Thanks to generous sponsoring I managed to make it to Bangalore for FOSS.IN and Girish kindly agreed to provide accomodation. It is really great to be in India again, to see the streets, the local market, catch up with friends from India and Europe. Girish is currently struggling with plugin code in QtWebKit for Mac, Win and X11 in both window and windowless mode, in the good ole wold and in QGraphicsView… I’m analyzing the loading behavior of a particular…
This week I had to make parts of OpenBSC work with TCH/H and use AMR. This work is needed for On Waves and when I say parts I mean the strict BSC subset of OpenBSC (in contrast to make the MSC code we have work as well). The first part is to make TCH/H work and that was easy as LaF0rge did almost everything to make it work. You have to change the OpenBSC configuration to use TCH/H instead of…
Currently I’m sitting in the nice offices of On Waves and when not trying to convince the embassy of India to give me a visa I’m working on OpenBSC. For this week I try to make call handling with the MSC rock solid.So far I have fixed some bugs, added features to OpenBSC, enabled A5/1 encryption, started using TCH/H, started using AMR, fixed bringup on nanoBTS coldstart and now I’m working on the MGCP to verify that I can hear…
I’m currently writing NEON code for the Qt PorterDuff SourceOver implementation. At the beginning one has to make the decision to use inline assembly, a seperate .S file or the ARM NEON Intrinsics. I have chosen to go with the ARM NEON Intrinsics embedded into C++ code for a couple of simple reasons. At first it is portable across gcc and RVCT doing a .S or inline assembly would not work for RVCT that is used by the Symbian people….
I’m working part time on improving the performance of QtWebKit (memory usage and raw speed) and I have created some tools to create an offline copy of a number of webpages (gmail, yaho mail, google, news sites…). Using these sites I have created special purpose benchmark reductions. E.g. only do the image operations we do while loading, while loading an painting, load all network resources. One thing I have noticed is that with a couple of small things one can…
I’m currently work on making QtWebKit faster on ARM (hopefully later MIPS hardware) and in my current sprint I’m focused on the painting speed. Thanks to Samuel Rødal my work is more easy than before. He added a new paintengine and graphicssystem that allows to trace the painting done with QPainter and then later replay that. Some of you might feel reminded of Carl Worth’s post that mostly did the same for cairo. How to make painting faster? The Setup…
One idea is in my mind. How can libmemusage.so, libmemintercept of memprof, memprof be merged into one and provide more and better results. E.g. sometimes you want to trace and get the profile when the heap maxes, or you want to have a histogram of allocations. It is possible to write C code for that and integrate it into one. On the other hand with technologies like DTrace one can easily write the histogram generation, profiling, etc with a trace…
Today I have released memprof 0.6.2. The most prominent change is merging a merge of raster’s timegraph for memory allocations and fixing various stability bugs introduced post 0.6.0. The code is currently located on gitorious and the release tarball is here and the shortlog can be seen below: Cristi Magherusan (2): some other minor changes, mostly guint -> gsize’s fixed a typo, bug #51556 in the gnome bugzilla Holger Hans Peter Freyther (10): mi-perfctr.c: Remove the O_CREAT (from the openSUSE…
We tend to write classes without really caring about what the compile will do to create the binary file. When looking into performance and specially memory usage and you create certain objects thousands of times it becomes interesting of how much memory one is wasting for padding/no good reason. The Linux kernel hackers wrote a tool called pahole that will analyze the DWARF2 symbols and then spit out friendly messages like the one below. struct Data { class QBasicAtomicInt ref;…