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To optimize bundling, set the following settings to Yes:
Static Files Settings -> Sign Static Files
How bundling works in Magento
The <exclude> entry in a theme’s etc/view.xml file tells Magento which files it should not bundle.
The following code snippet from Magento’s Luma theme shows the types of files you should exclude in your theme.
Setting bundle file size
The bundle_size entry controls the file size of the generated bundles.
Setting this to a large number will reduce the number of bundles generated, but the file sizes will be big.
A small number will increase the number of bundles generated, but the file sizes will be smaller.
You want to balance the number of files to download on a page with the size of the data.
A single connection should be around 100kb.
Fine tuning your theme
There are many ways to tune your theme’s etc/view.xml file.
For example, Magento’s Luma theme is configured to work well for all pages, but
by adding or removing items inside exclude, you can maximize browser performance for home, catalog, or product pages.
Create a blank page with the layouts you would like to tune.
Use the results of that comparison to build your exclude list.