slow swipe action with large galleries

Which gallery is being used does not matter – in the end Photoswipe will display all images in a lightbox, no matter where they come from.

Edit: yes, only regular WordPress galleries and Gutenberg gallery blocks are supported for separate lightboxes.

Do you have an example URL?

Here you can see a gallery with more than 200 images, which works fine on my browser – no delay, nothing is slower as usual:

https://arnowelzel.de/en/back-from-finland

If this is also slow for you, than you have a problem with your browser.

• This reply was modified 4 years, 3 months ago by Arno Welzel.

Thank you for your help and very quick response. Your page works ok at my end.
Here is my page with the most images on my site, if I try and swipe as fast as I have just done on yours noting happens, I have to drag my finger very slowly across to view the next image. My big gallery is at the bottom of the page.
https:
And here is one with only a few images that works fine.
https:
I have noticed with all my gallery’s the more images there are the slower the swipe has to be

• This reply was modified 4 years, 3 months ago by generalnumpty.

I’m sorry, but I can’t reproduce your problem on my computer. The big gallery on the first website works without any delays. On a mobile browser there are some delays before the lightbox will accept another swipe after – but usually not more than 1 or 2 seconds. So when you wait 2 or 3 seconds before swiping to the next image, there is no problem at all.

I believe that this can’t be avoided completely with very large galleries since Photoswipe has to load the images in the background so you can see them when swiping. Also I don’t know what I can change here, sorry.

However I did a quick test with Pingdom (https://tools.pingdom.com/fpt/) using UK as origin – and the page with the large gallery took nearly 10 seconds for only 35 requests, which is really slow. For comparison: my example at https://arnowelzel.de/en/back-from-finland only takes 1.8 seconds for 234 requests. Maybe there is a bottleneck on server as well which only gets noticable when using mobile devices which might behave different compared to desktop browsers.

• This reply was modified 4 years, 3 months ago by Arno Welzel.

Thank you so much for looking into this for me.
Yes on computer everything is ok.
I am seeing it on android phone and an android samsung tablet. Wonder if its an android thing. On the other hand your gallery is bigger than mine and your images are bigger also.And yet on yours I don’t even need to swipe – I can almost just flick to the next one.
Even when I wait I still am having issues getting the swipe to work unless I slowly smoothly move my finger across.
I will have to do some research (learning) about how to fix what pingdom is reporting.

Not sure what it means yet but I did a pindom test and both pc and phone result were almost identical apart from phone was 3.99s load time.
Performance grade B 88
Page size 475.3 KB
Load time 3.73 s
Requests 35

What does checking the “Add native lazy loading to images” do. checked and unchecked. I don’t see a difference.

Also a thought on “Photoswipe has to load the images in the background so you can see them when swiping.”
Is it loading them all or just the next 2 or 3- or 5 even.
I did search and could not find anyone with the same issue as me.

Thanks again.

EDIT
Just got a friend with an apple phone to test and its working fine, although they have never looked before, maybe its a cacheing issue.
I used to have an option on my back end site to delete cache but for some reason on an update perhaps its gone, so I will now need to install a cache app and clear and try.

• This reply was modified 4 years, 3 months ago by generalnumpty.
• This reply was modified 4 years, 3 months ago by generalnumpty.
• This reply was modified 4 years, 3 months ago by generalnumpty.
• This reply was modified 4 years, 3 months ago by generalnumpty.

An update, I have spent the day installing and optimising my site with lightspeed cache. Which has improved all the speed tests but the needing a slow wipe issue still exists.
Odd though I got another friend with an android phone to test and they have no issues but they run android 10 and I am on 9 ?

The swipe itself was ok. It just had the effect, that sometimes swiping will not continue and one has to wait 1 or 2 seconds, before the next swipe is possible. I also used Android 10 and tested this with Firefox and Chrome.

Unfortunately I deleted the notification e-email with the URLs and don’t have that any longer – if you like me to have another look you can also contact me via e-mail directly. You can find my address at https://arnowelzel.de/en/about-me

Email sent – thank you.

Hi @generalnumpty ,
Did you get any other conclusions on this? I have the same issue on a page with about 18 galleries (most are only 4 images each).
I also run Android 9 and it seems a little better on my wife’s Android 10 phone.
It seems to improve when I reduce the image size. For example, the galleries of 800x600px for example seem fine and flickable, whereas the galleries of 1200x900px require the slow drag. But these results were not 100% consistent. Also the 1200x900px galleries were farther down on the page.

One more observation: It seems like after a minute or two of browsing on the page, the flicks are becoming not possible and it requires me to slow drag. Not sure if it’s just something on my phone or my end. When I jump to a 1200×900 gallery right after opening the page, it’s fine, but even the 800×600 galleries are hard to swipe after some time of opening and closing images on the page.

Did you find which variables have the biggest effect or improvement to this for you?

Thanks,
Nate

• This reply was modified 4 years, 2 months ago by Nate.

I sent an email to Arno but he never replied I don’t hold it against him as Im sure he is really bussy and it is a great plugin.
My symptoms in a nutshell are the higher the number of images in the gallery the slower the swipe needs to be. My images are optimised to 1200×800 at between 40 and 100kb each.

I have resigned myself to thinking that it is something my end as I have asked a few other friends to test for me and so far everyone with an apple phone have no issues but maybe because they are all running the latest IOS 14.2. I have also asked friends with android 6 and they have no problems.

At my end I have a phone with android 7 and one with android 8 and both phones show the needing a slow wipe issue.
Then this–
I do also have a Samsung Tab A that was running android 9 and that too was showing the issue. I was then able to update the Samsung Tab from android 9 to android 10 and now I see that with android 10 there are no gallery slow swipe issues at all.

I do not recall noticing any issues a while ago – perhaps its something to do with latest WordPress updates and https/2 and older android not supporting it ???

Or maybe when I got the two phones the first time install I denied some option in the set up that I did not with the tab.
But I tried Arnu’s gallery on his website and I had no issues with swiping that.
My gallery are all made with Foogallery, arnu’s I belive is WP standard.

I have to admit I don’t know how to fix this issue at the moment. I can’t find out what is causing delays exactly. Just for clarification – some of my own galleries also have a lot of images and I don’t have any noticable delays. For example:

https://arnowelzel.de/en/jim-austins-computer-sheds

https://arnowelzel.de/en/england-2017

The gallery I use is the WordPress standard gallery with a custom output filter provided by https://www.ads-software.com/plugins/cleaner-gallery/ (as this plugin seems to be is no longer maintained, I may need to repace this with my own code, but so far it still works fine).

Another site which works fine: https://eyespeak.de/die-alte-schraubenfabrik/

Hi Arno. I have no trouble swiping those 3 gallery’s. I just don’t get what’s happening when it comes to mine and it seems it s only my two devices that have the issue. My galaxy tab did have the issue but after moving it from Android 9 to 10 it fixed it. Some one I know has android 6 and they have no issues aaaaah.

Thanks for the replies guys. Arno’s galleries also work fine for me.
Even just listening and keeping it in mind for a solution that may all of a sudden come to mind later, being honest that we’re not sure ATM is good support in my book.
Cheers!
Nate

HI Arno.
Did you ever manage to have time to visit my link that I sent you of a video I put on my website for you showing the exact issue.

Yes, I did. But I still don’t know how to fix this.