Hi again,
 
Now I have got some reasonable numbers to Apache log files, but there is still 
one thing confusing me. For each browser request I am getting two new blocks of 
data into the logfile. They look otherwise exactly alike, but timing values are 
not the same. Why do these blocks appear twise and should I add these values 
together to get the overall response time? For example in the case below, is 
the total time for GeoTiff thus (total time 1) + (total time 2) = 0.040 + 0.040 
s = 0.080 seconds, and for JPEG 2000 0.240 + 0.240 = 0.480 seconds? The times 
for these two blocks are not always the same even in this case they are.
 
Short explanation about this very first test. I set the map extents in a 
mapfile to 100 by 100 meters and image size to 200 by 200 pixels that equals to 
image pixels in my test image with 0.50 metre pixel size. The requested area 
was somewhere in the middle of the original image of size 10000 by 10000 
pixels. The source was in the first case in Geotiff format and in the other 
case in lossless JPEG 2000.  I made the request by browser with mode=map.
Please do not look too closely at the numbers yet (well, I guess that now you 
for sure will...). This case with corresponding number of image screen pixels 
seems to be extremely favourable for GeoTiff.  It might be correct to say that 
Mapserver in extreme case, which is when source image pixels correspond 
directly to screen pixels, can perform 6 times better with GeoTiff format than 
with JPEG 2000 but this has to be verified.
 
Regards,
 
-Jukka-
 
Below is the excerpt of the log file
 
Case geotiff:
msDrawRasterLayerLow(Geotiff): entering.\r
msDrawGDAL(): src=99,9699,201,201, dst=0,0,200,200\r
msDrawGDAL(): red,green,blue,alpha bands = 1,2,3,0\r
msDrawMap(): Layer 0 (Geotiff), 0.040s\r
msDrawMap(): Drawing Label Cache, 0.000s\r
msDrawMap() total time: 0.040s\r
msDrawRasterLayerLow(Geotiff): entering.\r
msDrawGDAL(): src=99,9699,201,201, dst=0,0,200,200\r
msDrawGDAL(): red,green,blue,alpha bands = 1,2,3,0\r
msDrawMap(): Layer 0 (Geotiff), 0.040s\r
msDrawMap(): Drawing Label Cache, 0.000s\r
msDrawMap() total time: 0.040s\r

Case JPEG 2000:
msDrawRasterLayerLow(jp2): entering.\r
msDrawGDAL(): src=99,9699,201,201, dst=0,0,200,200\r
msDrawGDAL(): red,green,blue,alpha bands = 1,2,3,0\r
msDrawMap(): Layer 2 (jp2), 0.240s\r
msDrawMap(): Drawing Label Cache, 0.000s\r
msDrawMap() total time: 0.240s\r
msDrawRasterLayerLow(jp2): entering.\r
msDrawGDAL(): src=99,9699,201,201, dst=0,0,200,200\r
msDrawGDAL(): red,green,blue,alpha bands = 1,2,3,0\r
msDrawMap(): Layer 2 (jp2), 0.240s\r
msDrawMap(): Drawing Label Cache, 0.000s\r
msDrawMap() total time: 0.240s\r
 
 

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