My problem is as illustrated in the above picture, where we can see a set of two font files being fetched and transferred twice.
These fonts are self-hosted for my Gatsby.js site, and this double-fetching leads me to see font flashes twice on page load. Some clues that might shed some light:
1) Lighthouse is complaining about this error being logged into the console:
"Failed to load resource: net::ERR_ACCESS_DENIED" with regards to one of the fonts (Open Sans).
2) The initiator for the second set of font requests is "other". A google search tells me that "other" refers to requests made from a user (which seems unlikely here since this is on page load) or for preloaded requests (I didn't explicitly include a preloaded link in my HTML head, but maybe one of those Webpack scripts?).
3) This issue only appears in my production build. It works okay and only fetches once in development mode.
Does anyone have any idea what might be causing this, or could perhaps give me some advice as to how I might even begin to debug this problem?
Related
hey guys i am having a problem that i see others with online but i am yet to find a fix for my website.
facebook not detecting my images as of a couple of hours ago, i tried disabling hotlinks in cloudflare, tried fb debuger and scrapping tool etc no solution.
example if you try to share this page, no picture appears: http://www.yardhype.com/12-year-old-jamaican-girl-wins-master-chef-junior-competition/
ERROR message
"Provided og:image URL, ........testsite/wblob/5433A6CF57A599/2803/3DF62/w3l6_ERf2C3ADvxqhgccQg/jasmin.png could not be downloaded because it exceeded the maximum allowed sized of 8Mb."
the image is not over 8mb
ALso correct url is shown in the raw tag area
When I opened that link http://www.yardhype.com/12-year-old-jamaican-girl-wins-master-chef-junior-competition/ I don't see the image regardless; I opened up Chrome's debugger and saw this:
A Parser-blocking, cross site (i.e. different eTLD+1) script,
http://ajax.cloudflare.com/cdn-cgi/nexp/dok3v=85b614c0f6/cloudflare.min.js,
is invoked via document.write. The network request for this script MAY be
blocked by the browser in this or a future page load due to poor network
connectivity. If blocked in this page load, it will be confirmed in a
subsequent console message.See
https://www.chromestatus.com/feature/5718547946799104 for more details.
So the way that page is displaying the image is likely not up to standards.
I have a Magento website and I have been noticing an increase in warnings from Catchpoint that various images, CSS files, and javascript files are taking longer than usual to load. We use Edgecast for our CDN and have all images, CSS, and JS files hosted there. I have been in contact with them and they determined that the delays happen when the cache for the resource has expired and it must contact the origin for an updated file. The problem is that I can't figure out why it would take longer than a second to return a small image file. If I load the offending image off our server (not from the CDN) in my browser it always returns quickly. I assume that if you call up an image file directly using the full URL to the image file (say a product image, for example), that would bypass any Magento logic or database access and simply return the image to you. This should happen quickly, and it normally does, but sometimes it doesn't.
We have a number of things in play that may have an effect. There are API calls to the server for various integrations, though they are directed at a secondary server and not the web frontend. We may also have a large number of stale images since Magento doesn't delete any images even if you replace them or delete the product.
I realize this is a fairly open ended question, and I'm sorry if it breaks SO protocol, but I'm grasping at straws here. If anyone has any ideas on where to look or what could cause small resource files, like images, to take upwards of 8 seconds to load, I'm all ears. As an eCommerce site, it's getting close to peak season, and I can feel the hot breath of management on my neck. Any help would be greatly appreciated.
Thanks!
Turns out we had stumbled upon some problems with the CDN that they were somewhat aware of and not quick to admit. They made some changes to our account to work around the issues and things are much better now.
We have deployed an MVC 3 website on an IIS6 box.
Everything runs fine, but the performance is abysmal.
Can anyone help me understand
why am I getting 20 second response times to get a script bundle?
why bundled scripts are not cached by IE even if the Expires header is set?
The site is several times faster in Chrome (I have noticed the cache behaviour is correct), but we cannot force customers to use it.
Any help would be great. I'm kind of wondering if it's a server-side setting that's forcing the bundle recompilation each request, or if it's just IE acting like usual.
Edit: as per comments request, I'm including also the bundle request headers:
If you have different download times for a full reload between the two browsers it could be that you are doing intense computations with a client side framework like angularjs (I have seen big performance differences from highly complex angularjs apps between the two browsers).
If both your browsers show the same download time, it is either a network issue, or a server issue.
The IE caching could be a separate issue, break your problem into two parts - look for the cause of the slow downloads first.
All I can do now is suggest an approach to finding the issue.
Summary of what you know
It looks like you have:
Server sends an Expires header one year from now
When you reload the page (i.e. you don't force a full refresh using Ctrl+F5)
IE doesn't take any notice of the cache header, and when it sends it's new request it doesn't use If-Modified-Since or If-None-Match
Chrome behaves differently and respects the Expires and/or ETag response headers (it doesn't even make the request again for the bundle).
EDIT 1: You also seem to be saying (though it would be good to see a timeline from chrome) that Chrome downloads the files faster, implying it is not a server-side problem. Your latest comment states that Chrome's downloads are also slow. (end edit)
And you also seem to be saying that this behaviour is consistent (i.e. 100 requests in IE, and 100 requests in Chrome show the above behaviour with no deviations).
Approach
You should break this problem into two parts:
Why is the download so slow?
Is there a server-side performance problem? Look for common download times in IE and Chrome, and Firefox (it could be due to bundling/minification/compression on the server).
Is there a network connectivity issue (dropped packets, for instance)? Look for inconsistent download times, Start times, Request times, between requests in a given browser and the same behaviour across all browsers.
Is a script slowing down IE, but not Chrome (this is not uncommon, I maintain legacy sites where the scripts don't run well in IE but do in Chrome) - look at different profile results between browsers.
Why is the javascript not being cached in IE? Troubleshoot (1) first, then worry about this.
It is possible that the two are related, but approaching them separately will be a start. Number 1 is far easier to diagnose that 2, the top references to caching javascript in IE on the web are to prevent it in order to help with development.
Root cause diagnosis
EDIT 1 The first thing to do is try the site from a browser on the server, or very close to the server to see if you have a network issue. (end edit)
Tools like Fiddler, the browser developer tools, timeline and script profiler, and YSlow are your friend. Compare each of the following between Chrome and IE (and see what happens in Firefox as well) and spot the difference. Note: you may need to clear the browser cache between tests.
browser developer tools -> script profile: see if you have a slow running script in IE compared to Chrome
similar analysis in a tool like YSlow (look for comparisons between the two browsers, not script improvements)
request and response headers, and timeline from a normal (i.e. not full reload) page load
request and response headers, and timeline from a full page reload (Ctrl+F5)
Start and Request durations for every js file for a given browser, and between browsers (this may point to network issues)? I note that the Start and Request alone are taking 0.6s and 1s each in IE - that is very very poor performance.
5 requests, and 5 full reloads with cache clearing between (that is, don't chase a ghost - be consistent in your test methodology)
Download times should be no different between Chrome and IE with no scripts actually running so also add a control test. Assuming that your bundle files don't "do anything" (i.e. they contain functions that the page calls rather than kicking off long processes by themselves) then create a blank page in your site which references exactly the same javascript files - not just the bundle, but every single js reference.
With the control test you can compare pure download times and caching behaviour in IE to Chrome, without any client side javascript running (use the developer tools profiler to verify no scripts are running). If your bundle files do kick off long running things, just temporarily disable those things by putting return statements at the top of the script and concentrate only on the download into the browser.
I've got a web service that, like most others, uses js and css files. I use the old trick of appending a version number to the js and css file like; ?v=123 and that gets changed every time we update the service on production.
Now, this works fine on all browsers, except for Chrome. Chrome seems to prefer it's cached version over getting the new one and therefor seems to ignore the appended variable. In some cases, forcing it to refresh cache (cmd+r / ctrl+f5) wasn't enough so I had to go into options and clear out the cache for it to load up the new content.
Has anyone experienced this issue with Chrome? And if so, what was the resolution to the problem?
Chrome should certainly treat requests with varying query strings as different requests; a cached result for style.css?v=123 should never be used for style.css?v=124. If you're seeing different behavior, please file a bug at http://new.crbug.com/ and post the bug ID here.
That said, I'd first check to see whether the page was cached longer than you expected. If a new version of the page itself wasn't downloaded, then it would still be requesting ?v=123 as the HTML wouldn't have changed. If you're sending long-lived cache headers with the page, it's certainly possible that Chrome is caching it more aggressively than you expected. If that's the behavior you're seeing, please star http://crbug.com/8742 for updates.
I had also same experience
You can user Ctrl + Shift + R for cache free browsing in both Chrome + Mozilla.
I have had this experience as well.
I run a membership site which displays content such as "You must be logged in as a Gold member in order to see this content" if they are not logged in or are trying to view content not allowed by their membership level. But even if the user is logged in, the user would still see "You need to log in", due to Google Chrome's aggressive caching. In Firefox, however, it works fine as I test logging in and out of all 5 levels of membership - each displaying the proper content.
While Chrome's caching problem can be solved by clearing the cache every time the user logs in and out, it would be really annoying to take that approach.
An issue has started recently, within Chrome and reportedly Firefox, pages would be loading fine and browsing would be as normal and then suddenly then a page would fail to load (continuing to spin as if loading). The page that fails is often not the same.
If I refresh the page or try to goto another page on the domain within the same browser, the browser doesn't even try to resolve the name or make a connection, and is then unable to load the page.
Swapping to another browser and I am back to browsing the domain normally again, while the original browser(in most cases Chrome) will not load the pages until a restart.
This has happened with 3 different people on 3 different machines in both Chrome and Firefox.
The domain that it is running off has allot of ajax calls within certain pages, I am not sure if the server is tripping out due to the number of requests from the one client...I am not sure.
I am not sure if this is a server, client or script functionality issue, as I can not personally reproduce it. I can do little to debug or work out what is causing this or how to fix it...
As you can see I am not sure of allot with this problem :) so I am throwing it out to stack-overflow in the hope that someone may have had similar experiences or have any directions I could look towards.
Cheers,
Brendan
If the page is making many requests in a short time, your firewall (router) may block it. I've noticed this behavior on my own router, and had to set it to a less restrictive level to make things work.