Thanks Jean

I'll try

Hi Jean
I'm using the image size medium, but other sizes used only px (0), this solved my problem with cache.
Since the problem of image pop up, I saw your post on another, saying that should change My_Site/template/My_template/html/com_k2/template/default/item.php.
Also solved.

Thanks
Nice to meet to

Well I'll tell you how I solved the huge cache that generates K2, first answering the question why K2 generates this huge cache.
When you insert an image in an item (article) K2 it generates around 6 copies of the same images with different dimensions, to more than 6 copies?
These copies are used in different locations of the Project.
Images small commonly used as pre visualization in the form of inserting pictures and also the K2 index of items (articles) of K2.
Larger images are in use in category view, and also in item (articles) of K2 itself.
Well it did to solve a mixture of solutions indicated by JeanRocha (JoomlaClube Brazil) and by Jean Philippe (K2 Forum) guided me.

1 Enter each item of K2 and removed the images (turn zero whole cache)
2 Define the size of the image I wanted to use in my case medium size and the other set 0px
3 I went into each item of K2 reinserting each image in your particular item. Generating a cache with only a picture and five other pictures less than 2k.
4 I disabled the pop up images of items (by clicking it appeared only a white square and x, for the image used in the pop up as imagemXL was set to zero, no image)

I deleted the line of code in bold:

<A class = "modal" rel = "{handler: 'image'}" href = "<? Php echo $ this-> item-> imageXLarge;?>" Title = "<? Php echo JText :: _ (' K2_CLICK_TO_PREVIEW_IMAGE ');?> ">
<Img src = "<? Php echo $ this-> item-> image;?>" Alt = "<? Php if (! Empty ($ this-> item-> image_caption)) echo :: K2HelperUtilities cleanHtml ($ this -> item-> image_caption); else echo :: K2HelperUtilities cleanHtml ($ this-> item-> title);?> "style =" width: <? php echo $ this-> item-> imageWidth;?> px; height: auto; "/>
</ A>

Located in my_site/template/my_template/html/com_k2/template/default/item.php

Before
Size-generated backup with Akeeba Images enabled - 112.79 mb

After
Size-generated Akeeba backup with the changes and images enabled - 32.55 mb