I have a very strange issue with Apache and Magento. Apache is very slow when serving images, but only for images in a particular folder of Magento theme.
Isn't an Apache issue because in the other 15 site hosted we haven't this issue.
Has you can see in the following image, the first image of 179kb in the directory www.site.com/img/ is downloaded in 115ms
The others images in www.site.com/skin/frontend/ultimo/default/images/ of 100-200kb, are downloaded in 1-1.5 seconds.
This makes the whole site very slow.
Where can be the issue?