So you can load css and such with javascript: https://www.geeksforgeeks.org/how-to-load-css-files-using-javascript/ https://stackoverflow.com/questions/574944/how-to-load-up-css-files-using-javascript
https://stackoverflow.com/questions/4724606/how-to-use-javascript-to-check-and-load-css-if-not-loaded/25615777 What I am doing is loading JSON like this. function loadjson() { xmlhttp = new XMLHttpRequest(); xmlhttp.timeout = 500; // time in milliseconds xmlhttp.onreadystatechange = function () { if (this.readyState == 4 && this.status == 200) { myObj = JSON.parse(this.responseText); //handle parsing json and updating fields } xmlhttp.open("GET", "/json", true); xmlhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded"); xmlhttp.ontimeout = function () { //exit and do nothing we will make another request // here if you are not doing a periodic load you could call function again to try again. } xmlhttp.send(); } setInterval(loadjson , 1000); On Sun, May 10, 2020 at 2:51 PM Mário Luzeiro <mrluze...@ua.pt> wrote: > Hi Trampas, thanks for sharing. > It was not clear, are you using some custom loading of resources (eg > script and css files) ? Or do you mean just data (such as JSON)? > Could you share details how that is performed? > I was looking for some way that I can manage the loading manually and > request each resource one by one instead of browser doing it.. > but I couldn't find a way. > > Unfortunately from what I search, there is no way to configure the > browsers how should they behave on loading the multiple resources files. > I tried some tags for preload etc and none made any effect (at leas in > firefox, where I was testing..) > > Mario > > ________________________________________ > From: lwip-users <lwip-users-bounces+mrluzeiro=ua...@nongnu.org> on > behalf of Trampas Stern <tram...@gmail.com> > Sent: 10 May 2020 13:21 > To: Mailing list for lwIP users > Subject: Re: [lwip-users] httpd, tls, multiple get requests, delays > > I have ran into similar issues. I ended up changing my HTML source files. > > To understand let me start with the background. I have a web page where > ever second I request data from the embedded server and display it. So in > the Javascript for the web page I had a 1000ms timeout that requested new > data(file). This worked great on the bench. However the customer was > testing it and complaining about it being slow. As it turns out the issue > was the customer had a slow laptop and when they started a zoom meeting the > network traffic on the laptop went up and my device got really really slow. > What I found was happening is I would make a request for data, it would > time out inside chrome which would retry the request. That is as the > requests timed out in the browser it would retry, this meant as time moved > forward I would start with browser trying to request one copy of data, then > if that timed out it would request it again while my timer in javascript > also requested it again, now I had two connections for the same file on the > embedded device. Then three, then four... > > The solution was to change the javascript such that it made request and if > I did not get a response in 500ms it would time out the request, before I > made a second request. This way at any time the browser would only allow > one request per file. I also could increase the timeout between requests to > match network speed. I found this also needed to be done with CSS files. > That is sometimes I found that I would get random failure requesting > files. For example at one time my Phy chip was getting too hot and causing > random network failures that cause havoc on my system. I found that this > would cause random failures, and retries. By having the javascript control > the time out on the file it helped. That is with the random failures and > the time out for the http connection in lwip I would again get where I had > two open connections for the same resource/file. Hence timing out on > javascript would send the close to the server and thus kill one connection > before starting a new one. > > This also leads to the other issue, when you use LWIP you have think about > how the system handles multiple requests for the same resource. That is if > you are sending out a file can lwip have two open connections to the file? > For example two computers accessing your server at the same time. This is > one reason I implemented authentication system, as it restricts the number > of connections, by restricting the number of users. > > Trampas > > > > On Sat, May 9, 2020 at 5:03 PM Mário Luzeiro <mrluze...@ua.pt<mailto: > mrluze...@ua.pt>> wrote: > Hello all, > > I'm looking for some ideas how can I improve an issue I have. > I have a httpd over TLS. As you may know, browsers fire multiple requests > at same time to get the resources. > > I had a lot of issues related with TLS / LWIP connections to handle this > multiple connections but the major are now working ok... > but as you can see in the screenshot, despite most of the requests are > handled very quickly but for some reason.. some will take too long to > handle. > There is some pattern on this, sometimes a bit random on the time it > takes.. > The first time the browser connects to the server it takes a lot to > initialize the TLS, but its ok because the next ones are very fast.. except > that random get requests > > Any idea how can it be improved ? > > I already support 20 TCP connections ( MEMP_NUM_TCP_PCB is 20 * 2 ) and > played with lots of parameters that I tuned for the best results except > this last one.. > > Regards, > Mario Luzeiro > _______________________________________________ > lwip-users mailing list > lwip-users@nongnu.org<mailto:lwip-users@nongnu.org> > https://lists.nongnu.org/mailman/listinfo/lwip-users > > _______________________________________________ > lwip-users mailing list > lwip-users@nongnu.org > https://lists.nongnu.org/mailman/listinfo/lwip-users
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