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Please help: Very slow "Start Render" time - Printable Version

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RE: Please help: Very slow "Start Render" time - Seph - 11-02-2015 01:00 AM

(11-01-2015 11:34 PM)Seph Wrote:  Is this because I'm using a child theme setup? Are you talking about the child theme css which is loading instead of the standard themes css? I wouldn't know how to use it, I just implented it in wordpress like it is standard.

For articles, the start render time is even worse, more than six seconds. And I have no idea why:


Getting rid of most of the images reduces the render time but it is really just not great:


It also varies a lot - between 1-2 seconds. The demo theme setup has even more images and renders way faster. According to the author, he just as caching active on a normal shared hoster.

RE: Please help: Very slow "Start Render" time - Seph - 11-02-2015 04:05 AM

Hm. I'm note sure what to make of the WBP results anymore. I just tested the verge from the frankfurt server (I'm sitting in frankfurt btw) and the speed result is pretty bad.


Now, if I'm actually surfing the page, it's super fast. So what gives? Weird.

RE: Please help: Very slow "Start Render" time - Seph - 11-02-2015 10:12 PM

Ok that is funny. Testing the page with Firefox instead of Chrome halves the start to render time. That seems like a pretty fast site now. What's going on!?


RE: Please help: Very slow "Start Render" time - akshayranganath - 11-03-2015 09:04 AM

I tried a run from US and can see the issue you seem to have hit. When testing from US, the pages appear to load pretty quickly.

Firefox: http://www.webpagetest.org/result/151102_DE_efbb506c311a564884f9eba21887692b/

Chrome: http://www.webpagetest.org/result/151102_P4_57a0e0f8c359483ec8469b28b5ac100d/

Do you have Real User Monitoring (RUM) enabled on your site? If you do, that should give you and idea on the real user's performance.

RE: Please help: Very slow "Start Render" time - Seph - 11-03-2015 05:43 PM

No, I haven't. But with that much difference in the testing results, what is there what you can learn from these tests? I spent hundreds of dollar to get better results, still, all I had to do is switching the testing server... Sad

RE: Please help: Very slow "Start Render" time - akshayranganath - 11-06-2015 11:01 PM

I spoke to a few people about the Wordpress and the response I have got so far is that you need to be very careful with using plugins on wordpress. Altough they exist, not every plugin is well tuned. Moreover, if you use more than one plugin, it will be hard to know the impact of how the different plugins interact. Finally, the plugins run at the time of generating response for the user. So, it should add to the overall page response time.

I know you are hard pressed to explain the situation and slowness. One of the ways to take this further is to do the following:
1. Start with pure wordpress and no plugins. Run WPT test and note it as your benchmark metric.
2. Start to turn on the plugins one by one and see the impact. If adding a plugin improves the performance keep it. Else disable it.

It is a trial and error situation - but, I think it will at least help you narrow down on the plugin that is causing performance issues.

RE: Please help: Very slow "Start Render" time - Seph - 11-06-2015 11:09 PM

It is enough to switch server region and chrome to firefox. Suddenly my render time is twice as fast. It seems like the WPT-Test isn't just that reliable, I guess.

RE: Please help: Very slow "Start Render" time - akshayranganath - 11-11-2015 04:22 AM

We ran some tests on another consulting work and found that the "start render" time on WPT is actually a reporting nuance that you need to consider.

The TTFB, as per the standard is just the time from the time request was sent to the time the first byte was received. For example, in this WPT test, the home page TTFB is 40 ms

However, the reported "First Byte" is a sum of the following:
DNS lookup + TCP connection + SSL handshake + TTFB. In the first request, this amounts to
32 + 30 + 128 + 40 = 230 ms. The reported "start render" time is 231ms.

So there are a lot of factors that could throw off your the reported value of the first byte time. However, I am not sure on why there is a variation by browser to that large extent.

RE: Please help: Very slow "Start Render" time - GreenGecko - 11-16-2015 03:30 PM

I'd say that all that's left now is for you to implement either SPDY or HTTP2 to improve the parallel downloading of files, and lose the wasted latency time on every file.

Alternatively you could look at combining css / js and using image sprites to reduce the number of files to be downloaded.

RE: Please help: Very slow "Start Render" time - Seph - 11-16-2015 04:47 PM

That is a server thing isn't it?