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<p class=MsoNormal>Hi,<o:p></o:p></p>
<p class=MsoNormal>I've noticed that the PNG and JPEG drivers in GDAL call theVSIFFlushL
function when finished writing a file. On Win32, this winds up at
FlushFileBuffers. Now, unless you're doing something transactional, or using
memory mapped files, or something of that nature, FlushFileBuffers is simply
not necessary, but it does have the penalty of forcing the disk to seek and
write. I noticed this when using GDAL to produce and cache map tiles to PNG and
JPEG files - you end up with a nasty serialization. I don't believe the TIF
driver does this, nor the BMP, but I haven't investigated others.<o:p></o:p></p>
<p class=MsoNormal>I can't see why exactly this call exists, but I'm pretty
sure they can be safely removed for the PNG and JPEG drivers, without any loss
of correctness. I'm not submitting a patch, because this change is so trivial.
And maybe there is some reason these things exist?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Ben<o:p></o:p></p>
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