Random Blank Pages – w3 total cache

ajoshi0, glad it helped you ?? Often solutions are really, really stupid simple, that’s why it’s hard to find them.
gooma2, yes, we know that. I did a lot of testing, logged in and out, asked many friends from around the world to check the site – logged in and out as well, from different browsers and clearing browser cache. Everything is working fine now. I’m not telling this fix will definitely help anyone in all possible cases, but it helped me and at least one more person. Seems like it’s worth a try.

I got my hands a bit deeper on this and my suggestion is that if there are some particular feature(s) not supported by your server config (or php config) but needed for debug mode to work properly, it encounters error / warning / notice or smth like that and stops execution. That’s why it writes a blank file to the cache. Definitely needs some more testing to find the roots but I don’t have time right now to do this. W3TC now works on my site and I’m happy.

I’ve been playing around with the W3TC settings after reading Ihor Vorotnov’s post. My suggestion above did stop the white screen, but when I ran GT Metrix, I got a score of 70 page speed and 87 yslow (I have 2000+ pages), which are not optimum scores. And page load speed of 3.77 seconds, which is not too, too bad – I had a site once where the page load speed was 24 seconds – yikes.

So I unchecked all options in debug mode – since it says at the beginning of the section “Performance in this mode will not be optimal, use sparingly and disable when not in use.” I’m not using debug mode, mainly because I wouldn’t know the first thing about it and ignorance is bliss…so I unchecked them all.

GT Metrix score was now 86 page speed and 89 yslow.

Then I turned off Amazon CDN.

Score was now 96 page speed and 90 yslow. I thought a CDN was supposed to improve site’s performance but my findings were not supporting that.

THEN, I turned browser cache back on (I just wanted to see if my changes somehow fixed the white screen also) and I added the 5G blacklist from this page https://perishablepress.com/5g-blacklist-2013/.

Final score is 96 page speed, 92 yslow, page load time 1.06 seconds (for 2000+ image-heavy pages, although all the above tests were just for the front page which is the most image-heavy).

I then tested it in Firefox after clearing cache and Internet Explorer which I haven’t used in weeks so there should have been no browser cache, and no white screen of death. I’ll check them again at the end of the week and see if my changes hold up. If I get the white screen again, then the browser cache is being turned off permanently.

hopefully that will help. I was getting excited at first too when I made a change the white blank screen went away, but then it would return within a day or two.

eventually one of the cache plugin developers will figure out what’s causing this across all of them.

njs7227, about this:

I thought a CDN was supposed to improve site’s performance but my findings were not supporting that.

It actually does. It makes pages load faster in most cases. Don’t rely only on scores. Every file hosted on CDN adds a redirect (request is actually made to a local origin and W3TC is redirecting it to CDN version). Google Page Speed, YSlow and other tools decrease your score because of that with a simple recommendation – ‘minimize redirects’. Check your site with https://tools.pingdom.com and review the results in detail.
Serving static files from CDN means that a user can send more simultaneous requests and download more files/assets at once. At the same time, serving large files from CDN decreases your server load, and it definitely improves overall performance, especially for high traffic websites. This makes a huge difference if you have short ping to CDN servers. I live in Ukraine, the closest and fastest S3 location is Ireland with 150-200ms ping. US locations are even slower. So, for any local ukrainian or russian visitor serving files from a local ukrainian server with 15-25ms ping will be much faster.

Im having still this same issue. It was gone but came back again after some days… we are pretty sure its a W3TC issue.
Pages que published but content isnt showed. You purge cache for that page and the content will come back. The problem is we are having this very often now. Purging cache wont help for that much, it will just fix the problem from published content but not for new content.

If there is no fix to this I will change the plugin ASAP.

After I unselected CDN, though, I could immediately tell my pages were loading faster even without knowing the “scores”. When I ran the GT Metrix, it only ended up supporting my feeling that not having the CDN improved performance – go figure. And regardless of the grade, a page load speed of 1.06 seconds is something I can live with.

luigidelgado, are you on shared hosting or vps? Have another idea to check. It’s working fine on my website but I already got my hand dirty on this issue, will try to figure out what’s wrong.

njs7227, seems we have the same scenario. You can check ping to your CDN and see if it’s high. But even with high ping CDN will be useful if your site receives high traffic – it will distribute requests and load. By high traffic I mean more that 1000000+ hits per day.

CDN can be your site’s lifesaver in pageload if you have a lot of images too! it can be how you have it set up too.

we have created 4 sub-domains on our site that are all connected through our MaxCDN Pull Zone. By having 4 subs, it breaks each one up for images, js & css so they’re pulling from those areas rather than just one spot.

When it comes to measuring page speed, you’ll usually wind up with different scores on each place you test.

Ihor: I have a cloud/ dedicated cluster. The thing is its a local news site and its having this issue very often.

In my case I do have CDN connected but in my case we are using Cloudflare Business.

So if I disconnect CDN (i have cloudflare plugin also) could this issue fade away?

luigidelgado, in your case I really don’t know and can’t even reproduce your environment. My recent idea was in completely different direction, it’s not your case. Already tested it, didn’t worked (

Regarding how I fixed this WSOD for my website – I actually managed to make it work fine with CDN. Disabled it just because it’s too slow for my region (local ukrainian and russian traffic). CDN wasn’t causing that WSODs. Turn off all caches one by one. Than turn them back on one by one, but, as soon as you check the “Page Cache” checkbox, BEFORE saving settings scroll down to DEBUG section and uncheck everything (the first checkbox is being turned on by default, as I noticed). Then save settings and countinue turning on all other caching methods you use. After that clear and rebuil all caches. It worked in my case, tried this several times. Restored DEBUG, got those WSODs again, repeated described steps – and everything is working again.

None of these solutions work for me. I installed and it was working great for 2 days. Then I activated another plugin, and that was it. I removed all the file, reinstalled, click activate, and then just blank.

I hope there is a solution to this.

I was researching on optimizing website performance and load speed and found an interesting hint. While this is not related to the WSOD bug, it may be useful for njs7227 and everyone else using CDN.

First, if you map your CDN service or S3 bucket to your subdomain you will have redirects.

Second, browsers will prefetch DNS only for your subdomain, not the actual location of a file. You will have non-prefetched DNS lookups, it can significantly decrease load speed, especially if you have many files linked to CDN.

The solution:
Let’s say you have files.domain.com.s3.amazonaws.com mapped to files.domain.com. In your HTML add this tag to your HEAD section right after the charset definition:
<link rel="dns-prefetch" href="//files.domain.com.s3.amazonaws.com">
This will tell browser to prefetch DNS lookup of this domain address, and when the actual request and redirect is made, the DNS lookup part will be skipped (it’s already prefetched) making it respond faster.
Tested, it really helps.

I’m not sure yet how Amazon serves this subdomain internally, right now testing if adding one more prefetch link for s3.amazonaws.com will make it even faster.

@pwizard this has been the issue. it only seems to work when you either make a slight change in the plugin or clear the cache.

naturally a caching plugin is rendered obsolete when it requires the user to constantly clear out the cache for it to work properly…

I’ve even submitted a bug report with no response and I’ve been a paying customer of them too this year!

@frederick Townes

I’m using the latest versions of WordPress and W3 Total Cache, and I have the same problem. (Theme Genesis + eleven40 Child Theme)

Is there some foresight to fix this problem?

Thanks

I’ve given up on this. Is seemed to work again for a while, now public home page is just blank. Great plugin when it works, but obviously useless since it doesn’t. Off to try another solution