Magento Image Cache Storage Requirements

Published: March 5, 2020


Recently I’ve been working with a client whose server is running low on disk space. I found that their media/catalog/product folder was 174 GB, 128 GB of which was in media/catalog/product/cache. This seemed like a lot to me, so I did some quick math and realized that the size of their image cache was nearly 3X that of the total size of the source images. This made me curious…what does this ratio look on other Magento installations? I decided to do a little research on this and wanted to share my findings.

The Data

The table below contains my findings:

Site Total media/catalog/product Total media/catalog/product/cache Cache vs Source Percentage
1 23 GB 4.7 GB 25.68%
2 250 GB 113 GB 82.48%
3 7.5 GB 4.9 GB 188.46%
4 2.1 GB 1.5 GB 250.00%
5 174 GB 128 GB 278.26%
6 57 GB 47 GB 470.00%
7 2.2 GB 2.1 GB 2100.00%

Per the table, the median image cache was 2.5X the size of the source images, meaning that the client in question was not unusual at all.

In the course of this research I also came across this git commit. It looks like in Magento 2.4 it will be possible to offload image resizing to a 3rd party such as Fastly. This should significantly decrease the overall media storage burden for merchants running Magento.

Max Chadwick Hi, I'm Max!

I'm a software developer who mainly works in PHP, but loves dabbling in other languages like Go and Ruby. Technical topics that interest me are monitoring, security and performance. I'm also a stickler for good documentation and clear technical writing.

During the day I lead a team of developers and solve challenging technical problems at Something Digital where I mainly work with the Magento platform. I've also spoken at a number of events.

In my spare time I blog about tech, work on open source and participate in bug bounty programs.

If you'd like to get in contact, you can find me on Twitter and LinkedIn.