SiteGround With WP Rocket – Does It Make a Difference? Is It Worth It?
- By
- 14 Comments
If you’re hosting your WordPress site with SiteGround, you get multiple ways to optimize its performance. You get built-in caching via SiteGround’s SuperCacher, and they also offer a companion SG Optimizer plugin to make other performance tweaks.
So, if you’re already using those tools, do you need to do anything else to optimize your site? More specifically, does it still make sense to use a comprehensive WordPress performance plugin such as WP Rocket?
In this post, I’m going to try to answer that question with real data. First, I’ll explain exactly what’s happening with SiteGround’s optimization, as well as how WP Rocket fits in. Then, I’ll run a bunch of performance tests to try to figure out if WP Rocket makes a difference.
What’s the Difference Between WP Rocket and SiteGround’s SuperCacher?
On their GrowBig and GoGeek plans, SiteGround include their own SuperCacher caching solution, as well as a free SG Optimizer companion plugin, which is listed at WordPress.org.
Before I get to the testing, let’s compare what the SuperCacher functionality and SG Optimizer do, versus what WP Rocket does.
SiteGround SuperCacher and SG Optimizer Explained
SiteGround’s SuperCacher adds three levels of caching:
- Static Cache — stores your static files, including images, CSS, JS and so on, in your server’s RAM, which means they’re served from RAM instead of your hard drive.
- Dynamic Cache — this offers full-page caching powered by Nginx, and is equivalent to what most WordPress page caching plugins do (including WP Rocket, though the exact mechanism is different). It takes the end-product of WordPress’ PHP and stores it as a static HTML.
- Memcached — this is object caching. It lets you store database queries in the cache, so you can deliver data from there, rather than querying your database each time.
In addition to the SuperCacher, SiteGround also have their own free SG Optimizer plugin, which comes installed by default with all new WordPress installs at SiteGround. This plugin integrates with the SuperCacher functionality to let you control your cache settings from your WordPress dashboard, and it also adds a bunch of other performance improvements, such as:
- GZIP compression
- Browser caching
- Minification and concatenation
- Image optimization
- Lazy loading
You can learn more about SiteGround in our full SiteGround review.
WP Rocket Explained
WP Rocket is a popular WordPress caching and performance plugin.
It adds page caching, as well as a huge number of other performance tweaks. Some of these tweaks are also offered in the SG Optimizer plugin, but you also get unique features.
It offers:
- GZIP compression
- browser caching
- minification and concatenation
- lazy loading
- CDN integration
- Heartbeat API control
- database optimization
- optimization for Google Analytics and Facebook Pixel scripts
- a bunch of smaller tweaks, such as disabling emojis.
It also gives you more control over how your cache functions, with features such as:
- cache preloading, which lets you automatically load your content into the cache, so every visitor gets served cached content
- separate caches for mobile users and/or logged-in users
You can learn more in our full WP Rocket review.
Can You Use Both at the Same Time? How Does It Work?
Yes! That’s the beautiful thing, and kind of the point of this post. The two are fully compatible, so you can use all three levels of SiteGround’s caching and the SG Optimizer plugin, while also using all of WP Rocket’s functionality.
Unlike our WP Engine with WP Rocket post, WP Rocket does not disable its page caching when you use it with SiteGround’s SuperCacher.
Instead, your site will have both full-page caching via Nginx at the server level (SiteGround), as well as page caching at the file/application level (WP Rocket).
When someone visits your site, your server will first try to serve the page from the Nginx cache. However, if the page isn’t in Nginx’s cache yet, then WP Rocket can serve it from WP Rocket’s page cache instead (which is totally possible because of how WP Rocket includes cache pre-loading). So, instead of the Nginx cache miss resulting in a visitor seeing an uncached page, they still get served a performance-optimized cached page from WP Rocket.
Additionally, WP Rocket’s purge functionality integrates with SiteGround’s cache. That is, if you purge the cache via WP Rocket, WP Rocket will purge both SiteGround’s Nginx cache and WP Rocket’s cache.
While there are no compatibility issues with the caching functionality itself, there is some overlap with some of the other performance features in the SG Optimizer plugin.
If you opt to use both WP Rocket and SG Optimizer, you’ll want to disable GZIP compression and browser caching in the SG Optimizer plugin because WP Rocket applies those optimizations by default.
In fact, SiteGround will automatically disable any overlapping functionality for you, as I discovered when I uploaded WP Rocket to my SiteGround site:
You’ll still be able to use a ton of other WP Rocket features, including:
- separate cache for mobile devices or logged-in users
- optimize CSS delivery
- lazy loading
- replace YouTube iframe with image
- database optimization
- Heartbeat control
- Etc.
What I’m Testing
To figure out how much value WP Rocket adds vs SiteGround’s built-in caching and optimization solutions, I’m going to test two scenarios:
- SiteGround with just the SuperCacher (all three levels) and SG Optimizer plugin. I’ll activate all of the other optimization features, including minification, GZIP compression, and lazy loading.
- SiteGround with SuperCacher, SG Optimizer, and WP Rocket (I’ll disable any overlapping features to avoid compatibility issues).
My test site uses a full demo from the Avada theme, which should do a good job of simulating a real WordPress site. You can see a full screenshot of the test page here.
Basically, I’m trying to answer the question: Is there any performance value to using WP Rocket on top of the optimizations you already get with SiteGround?
To gather the test data, I’ll use WebPageTest with the following configuration:
- Test location: Chicago.
- Connection Throttling: Fios 20/5 Mbps (which is about the average internet speed in the USA).
For each scenario, I’ll run ten separate tests on three different days — 30 tests total for each scenario. Then, I’ll put all of the data together at the end and try to draw some conclusions.
Day One Results:
Only SuperCacher and SG Optimizer:
Mean Load Time: 3.46 seconds.
| Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| 3.404 s | 4.118 s | 3.969 s | 4.394 s | 3.048 s |
| Test 6 | Test 7 | Test 8 | Test 9 | Test 10 |
| 3.391 s | 3.464 s | 2.821 s | 3.204 s | 3.669 s |
After activating WP Rocket:
Mean Load Time: 4.15 seconds.
| Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| 5.510 s | 2.954 s | 4.422 s | 4.674 s | 3.058 s |
| Test 6 | Test 7 | Test 8 | Test 9 | Test 10 |
| 2.755 s | 3.312 s | 4.139 s | 4.993 s | 5.657 s |
Day Two Results:
Only SuperCacher and SG Optimizer:
Mean Load Time: 3.95 seconds.
| Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| 3.809 s | 5.081 s | 4.291 s | 3.714 s | 3.415 s |
| Test 6 | Test 7 | Test 8 | Test 9 | Test 10 |
| 2.811 s | 3.259 s | 2.954 s | 3.425 s | 6.749 s |
After activating WP Rocket:
Mean Load Time: 3.33 seconds.
| Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| 4.789 s | 3.153 s | 2.979 s | 3.985 s | 2.682 s |
| Test 6 | Test 7 | Test 8 | Test 9 | Test 10 |
| 3.845 s | 2.646 s | 3.700 s | 2.757 s | 2.764 s |
Day Three Results:
Only SuperCacher and SG Optimizer:
Mean Load Time: 3.63 seconds.
| Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| 3.622 s | 3.859 s | 4.284 s | 3.361 s | 3.129 s |
| Test 6 | Test 7 | Test 8 | Test 9 | Test 10 |
| 3.525 s | 3.304 s | 4.372 s | 3.539 s | 4.214 s |
After activating WP Rocket:
Mean Load Time: 3.43 seconds.
| Test 1 | Test 2 | Test 3 | Test 4 | Test 5 |
| 3.811 s | 2.661 s | 3.640 s | 2.836 s | 3.643 s |
| Test 6 | Test 7 | Test 8 | Test 9 | Test 10 |
| 3.291 s | 5.766 s | 2.873 s | 3.318 s | 2.490 s |
Putting it Together: Is it Worth Using WP Rocket with SiteGround?
Okay, so after running 30 separate tests on three separate days for each situation, here’s how things shook out:
| Overall Average | Day One Average | Day Two Average | Day Three Average | |
| Just SG Optimizer | 3.68 s | 3.46 s | 3.95 s | 3.63 s |
| SG Optimizer + WP Rocket | 3.64 s | 4.15 s | 3.33 s | 3.43 s |
Those numbers are pretty dang even, which leads me to believe there’s not a big difference between just going with SiteGround’s SuperCacher and the SG Optimizer plugin, versus using WP Rocket.
WP Rocket certainly didn’t have a negative impact, but I’m not sure I can call that 0.04 second improvement significant.
So, from purely a page load time perspective, I’d say you don’t need to spring for WP Rocket if you’re already hosting with SiteGround.
However, I do think there are a few things that aren’t represented in the test data that may still make WP Rocket a good option to pair with SiteGround.
SiteGround Don’t Have Cache Preloading
Before running all of these tests, I opened the test page in my own Incognito browser to give SiteGround a chance to load the page into their cache. However, that won’t always happen in real life, and on a live site you’d have some people hit uncached pages because SiteGround don’t do cache preloading.
However, WP Rocket does, which eliminates that situation. Remember — if you combine WP Rocket with SiteGround’s caching, you basically have two levels:
- SiteGround’s Nginx caching at the server level.
- WP Rocket’s page caching at the file/application level.
So, because WP Rocket has already preloaded your content into its cache, it can still serve up a quick-loading cached page even in situations where SiteGround’s Nginx cache misses.
WP Rocket Still Does More Than SG Optimizer
Second, WP Rocket still just plain does more than SG Optimizer, even if those tweaks didn’t translate into big differences in the page load tests.
For example, WP Rocket adds extra features, such as Heartbeat API control and database optimization, which SG Optimizer doesn’t have. WP Rocket can also help you to optimize third-party tracking scripts, such as Google Analytics and Facebook Pixel.
Verdict
If you’re already using SiteGround’s SuperCacher and SG Optimizer, WP Rocket definitely isn’t a must-have plugin for performance. However, it still does offer some small improvements, so, if it fits your budget, it still may be worthwhile pairing the two.
And, again, the two are built to integrate with each other, so you won’t hit any compatibility issues in doing so. SG Optimizer will automatically disable its duplicate features to avoid a conflict, and you’ll also be able to purge the SiteGround cache through the WP Rocket interface.
Used/using SiteGround or/with WP Rocket? Thoughts or opinions?
By
TOP DEALS
Leave a Reply
All comments are held for moderation. We'll only publish comments that are on topic and adhere to our Commenting Policy.
Great article! The SG Opt works fine in one of our sites,.. but in one particular site not working at all .. No Improvements in page speed insights… We tried all other Plugins like Litespeed cache.. autoptimization .. but still, the site speed is struggling…
Hi Colin,
I just found this older post of yours. I am curious to know if, in your experience, this combination is still relevant in March 2021.
I am also tying to improve a site using the the Divi Theme. I was using W3TC and for all intents and purposes in real world eyeballing page loads it seems to work fine…till GTMetrix using the new Lighthouse setup tells you other wise.
I just installed WP Rocket as an alternative to W3TC after hearing great things about it and it seems to solve the GTMetrix results, though this can vary from day to day.
I will try your suggestions above.
This article reviews an older version of SG Optimizer. Now, there’s no need to combine it with WP Rocket anymore and actually I would advise against it. SG Optimizer has all the performance optimizations your site needs and you should totally go only for it to get the best loading speeds for your site unless there’s a very speciffic case in which your site doesn’t play well with our NGINX full page caching :)
I’ve been using both plugins for a while. Actually, the combination Wp Rocket + SG Optimizer does not make sense. The load speed almost stays the same as SG Optimizer or WP Rocket alone. However, you may need some other Wp Rocket features like database optimization, heartbeat control, CDN integration, etc. Otherwise, SG Optimizer is the only cache plugin you need, and, BTW, it’s free!
I recently had a plugin conflict experience with SG Optimizer and WP Rocket enabled both of them at the same time. Removed WP, and the website went back to working fine.
There are some conflicts when using SG Optimizer with ep rocket.
There are some conflicts when using SG Optimizer with Cloudflare. In SG Optimizer, go to the Frontend Optimization tab at the top and turn off everything.
Thanks for your interesting findings. Wondered if anyone can comment on the following as I ponder use of WP Rocket.
Like a few others out there I have suffered from using the SG Optimizer plugin on an eCommerce site.
Had various problems with pages excluded from SG Optimizer like images not loading (despite not using Lazy Load), Stripe payment fields being hidden, and just recently MemberPress system First/Last Name fields not passing data to database! Lost quite a few sales it appears over time.
I have progressively switched all SG Optimizer options off, and now, with the First/Last Name issue had to deactivate the SG Optimizer plugin altogether.
Using Cloudflare, with Cache OFF, but need to use some page rules for site forms to remove from cache. Not done yet so likely more form problems?? But limited rules on CF free plan.
So, been looking at WP Rocket to get back to a cached solution using the SG server cPanel caching tools, and then exclude forms pages with WP Rocket – assume it does that Ok.
Questions:
Anyone else out there having such trouble with SG Optimizer plugin?
Anyone just using Cloudflare cache without SG plugin but using SG cPanel caching tools?
Would Cloudflare with backend SG cache work as well as WP Rocket?
I’ve had a number of issues with Siteground’s SG Optimizer which forced me to go back to using WP Rocket.
Basically if you’re pulling any JSON calls via an API within WordPress, SG Optimizer will mess this up and disable functionality on the pages that require it. Unfortunately, their page exclusion option doesn’t seem to work well enough to prevent this from happening.
Secondly, on GoGeek plans you are limited to only 4000 CPU seconds per hour so you have to limit the WordPress Heartbeat as well, something SG Optimizer doesn’t do very well at either. If you don’t adjust this option, they will throttle your resources and your site will crawl to a standstill. Thanks Siteground!
However, when using WP Rocket, you need to turn off the Cache Pre-loader option that use dynamic pages as it will quickly eat up your allowance of 4000 CPU seconds per hour.
If you can manage these things in the confines of their hosting, you should be fine.
On a side note, since they have moved to a NGINX hosting platform, many of the features you were used to having via a cpanel environment are no longer available to you and that sucks because sometimes you need more control over things that NGINX prevents you from doing. If I wanted that type of hosting I would go sell my soul to Flywheel or WP Engine, which I don’t want to do.
Many thanks for your superb analysis, Colin. You answered the exact question that I had!
I recently had a disastrous experience with SG Optimizer and WP Rocket enabled at the same time. I’m still not exactly sure what the problem was, but my site would fluctuate from 1.9 seconds to 55 seconds load times! Removed SG, went back to working fine…
Awesome, exactly what I was looking for. I am unsing both SG and WP Rocket combined. Works fine. Thank you!
Great article! One final comparison would be great to add to your test results > How fast does the site load with only WP Rocket installed and not using SG SuperCache at all? That’s what we’re currently doing, so I’m interested to know what the difference would be.
I’ve been a long time WP Rocket fan and use it on several WordPress sites.
I recently moved one of these sites to SiteGround, and my initial testing shows no gain (worth mentioning) with WP Rocket enabled.
Great info about the topic, this may be a great combination for a website. thanks for the amazing info!!