[FFmpeg-devel] PIC and YASM
Tue Nov 10 01:26:41 CET 2009
On Mon, Nov 9, 2009 at 10:45 AM, Michael Niedermayer <michaelni at gmx.at>wrote:
> On Mon, Nov 09, 2009 at 10:12:12AM -0800, Frank Barchard wrote:
> > An upside is that code can load faster, since there are no relocs,
> just curious, do you have a benchmark about this?
Sorry, no.. someone else evaluated that. Best I can do is tell you the
current performance of loading ffmpeg on Vista
 DLL loadtime 1.21 ms, avcodec-52.dll
 DLL loadtime 0.33 ms, avformat-52.dll
 DLL loadtime 0.05 ms, avutil-50.dll
> > and take
> > less memory by sharing dll's.
> and do you have some numbers about this?
260k per tab in Chromium
> PIC code is inherently larger and more complex, it does require
> additional indirection tables, ...
> thats a cost everyone who uses it, has to pay.
Is that for global / static variables that you write to? For read only
data, you can use RIP.
> The win just happens for thouse who have 2 "dlls" loaded at the same time
> by 2 processes
> (this also implicates that libav* isnt linked statically like many do)
> and its just the pages that contain relocs that would differ
> and then only on OSs that cannot place these libs at the same location in
> both processes. (if the locations match, so do the relocs)
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