Large TIFF files always cached to disk

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mpetrovic72

Large TIFF files always cached to disk

Post by mpetrovic72 »

I have problems with large TIFF files (410 MB large).
The pc has 4 Gbyte of RAM (used: +/- 150 MByte, free: +/- 3.800 MByte),
but when I try to rotate the images, they are always cached to disk.
A 210 MB image is nicely cached in memory (fast, max. 1 minute to rotate), but a 410 MB is always cached on disk (slow, hours to rotate).

command:

convert.exe -monitor -debug cache source.tif -rotate 90 target.tif

open source.tif[0] (anonymous memory, 9924x14043 531.627mb)
load image: 100%
memory => disk


setting a higher memory limit does not help.

convert.exe -limit memory 2000 -monitor -debug cache source.tif -rotate 90 target.tif


I use ImageMagick 6.3.1 - 7 Q8
on a Windows XP Proffesional PC

thanks in advance.
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magick
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Post by magick »

Try adding -limit area unlimited -limit memory unlimited to your command line. You might have better luck under 64-bit Windows OS. Win32 sometimes won't give the memory ImageMagick requests even if its available.
mpetrovic72

Speed up disk cache

Post by mpetrovic72 »

I'm affraid it didn't help.
I have another question.
Is it possible to speed up the disk cache.

When we rotate 210 MB images (rotated in memory) we can hear the hard disk working. But when we rotate a 410 MB image (rotated on disk) we cannot hear the hard disk. When we look at the CPU usage, convert.exe only uses 0% - 1%.

thanks in advance.
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magick
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Posts: 11064
Joined: 2003-05-31T11:32:55-07:00

Post by magick »

To speed up the disk cache you oculd upgrade your disk to a 15,000 RPM SAS disk and you'll get additional speed-ups running under Linux rather than Windows. You can track the progress of the disk cache by adding -debug cache to your command line.
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