Is anyone here receiving an incredibly high Initial server response time? We're seeing upwards of 1.5s, however when using network tools, the server response time is sitting at < 150ms, so unless Google is doing these speed tests from a cave somewhere in the Amazon, we can't figure it out.
With the upcoming changes to ranking based on these arbitrary scores, does anyone have any insights here?
I'm experiencing very inaccurate performance measurements from Page Speed insights. is disappointing there is such little detail about the timing and network requests happening. The TTFB when running via their website is like 16s but when I test from nearly anywhere else, including via a proxy on the other side of the world, through tor, etc, the real TTFB is like 190ms.
There are problems with page speed insights that Google is not handling. So I suppose my answer is it's a disappointing and inaccurate tool.
All of that said, I would suggest trying the built in lighthouse tool inside chrome dev tools, this will show better scores for performance, but the outstanding question is how is google themselves measuring my websites performance?
Related
my website (www.scaredycut.com) loads very slowly. According to a load test, the initial "wait" is a long bottleneck. It ranges between 600 and 1900 ms.
Google's PageSpeed Insights test says:
In our test, your server responded in 0.59 seconds. There are many
factors that can slow down your server response time. Please read our
recommendations to learn how you can monitor and measure where your
server is spending the most time.
Google's recommendations don't tell you how to measure or get to the bottom of the problem. Does anyone have any suggestions as to where I should start? Should I contact my host?
Thanks for the help.
You need a complete PageSpeed overhaul and are you on cheap cloud hosting? Cuz your actual .com is taking over 2 seconds to load on its own without files.
Install w3 total cache and see how it does after activation vs without.
I'm developing a service where people can stream multiple audio files at the same time.
Unfortunately, when streaming about 4 streams simultaneously, Chrome's HTTP connection limit seems to kick in: new stream requests only arive at the server when a previous connection was closed.
Interestingly enough, I can play 10+ videos at the same time on YouTube.
What kind of technique could YouTube have used here to circumvent the browser's simultaneous http connection limit?
The crucial point here I suppose is that YouTube streams are not directly controlled by the browser, they are embedded Flash players which use streams that are handled by Flash. If you want to hand off the streaming process to an external app/library (Flash, Java etc) you can circumvent these limitations quite easily.
The other point is that YouTube has a huge CDN, so there is no guarantee you're getting any two videos from the same server, which would also help to circumvent concurrency limitations (to a point, at least).
I'm not surprised that Chrome stops you after a while because Google did a load of research and experiments regarding browser concurrency and relative efficiency a while ago, and I remember reading somewhere that they concluded that 3-4 concurrent connections to the same server represented the the most efficient data transfer architecture over straight HTTP. Annoyingly, I can't find a reputable source to reference with that (although I got it from one in the first place), however this is related and probably part of the same research program.
This is also the sort of research Facebook get quite heavily involved in, and you might find some useful information in over at http://developers.facebook.com/ if you can be bothered sifting through the rubbish to find it...
I'm profiling a asp(classic) web service. The web service makes database calls, reads/writes to files, and processes xml. On a windows server 2003 box(2.7ghz, 4 core, 4gb ram) how many requests per second should I be able to handle before things start to fail.
I'm building a tool to test this, but I'm looking for a number of requests per second to shoot for.
I know this is fairly vague, but please give the best estimate you can. If you need more information, please ask.
95% of the performance of any data-driven app is dependent on the database: 1) the way you do your calls, 2) the indexes, 3) the hardware under the database (disk subsystem in particular).
I have seen a machine, like you are describing, handle 40 requests per second (2500/minute), but numbers like 10 per second (600/minute) are more common. I would expect even lower if you are running your DB on the same machine, and even lower still if that DB is SQLExpress or MSAccess.
Also, at capacity, your app will probably not fail, but IIS will Queue requests, once it is saturated, and may timeout some of those requests if it can't service them before the timeout expires.
Btw, instead of building a tool to test your app, you may want to look into using a test tool such as Microsoft WCAT. It is pretty smooth and easy to use.
How fast should it be? Fast enough.
How fast is fast enough? That's a question that only you and your users can answer. If your service is horrifically inefficient and keeps up with demand, it's fast enough. If your service is assembly-optimized, lightning-fast, and overwhelmed with requests, it's not fast enough.
If the server is handling its actual workload, then don't worry about how fast it "should" be. When the server is having trouble, or when you anticipate that it soon will, then you should look at improving the code or upgrading the hardware. Remember Knuth's Law – premature optimization is the root of all evil. Any work you do now to make it faster may never pay off, and you may be forced to make compromises with flexivility or maintainability. Remember, too, an older adage – if it ain't broke, don't fix it.
Yes I would also say 10 per second is a good benchmark. For a high performance app you would want to get more than this, but if you have no specific goal you should generally be able to get at least 10 requests per sec for a general web page with a bunch of database queries.
I am looking for suggestions on doing some simple monitoring of an ASP.Net web farm as close to real-time as possible. The objectives of this question are to:
Identify the best way to monitor several Windows Server production boxes during short (minutes long) period of ridiculous load
Receive near-real-time feedback on a few key metrics about each box. These are simple metrics available via WMI such as CPU, Memory and Disk Paging. I am defining my time constraints as soon as possible with 120 seconds delayed being the absolute upper limit.
Monitor whether any given box is up (with "up" being defined as responding web requests in a reasonable amount of time)
Here are more details, things I've tried, etc.
I am not interested in logging. We have logging solutions in place.
I have looked at solutions such as ELMAH which don't provide much in the way of hardware monitoring and are not visible across an entire web farm.
ASP.Net Health Monitoring is too broad, focuses too much on logging and is not acceptable for deep analysis.
We are on Amazon Web Services and we have looked into CloudWatch. It looks great but messages in the forum indicate that the metrics are often a few minutes behind, with one thread citing 2 minutes as the absolute soonest you could expect to receive the feedback. This would be good to have for later analysis but does not help us real-time
Stuff like JetBrains profiler is good for testing but again, not helpful during real-time monitoring.
The closest out-of-box solution I've seen is Nagios which is free and appears to measure key indicators on any kind of box, including Windows. However, it appears to require a Linux box to run itself on and a good deal of manual configuration. I'd prefer to not spend my time mining config files and then be up a creek when it fails in production since Linux is not my main (or even secondary) environment.
Are there any out-of-box solutions that I am missing? Obviously a windows-based solution that is easy to setup is ideal. I don't require many bells and whistles.
In the absence of an out-of-box solution, it seems easy for me to write something simple to handle what I need. I've been thinking a simple client-server setup where the server requests a few WMI metrics from each client over http and sticks them in a database. We could then monitor the metrics via a query or a dashboard or something. If the client doesn't respond, it's effectively down.
Any problems with this, best practices, or other ideas?
Thanks for any help/feedback.
UPDATE: We looked into Cloudwatch a bit more and we may focus on trying it out. This forum post is the most official thing I can find. In it, an Amazon representative says that the offical delay window for data is 4 minutes. However, the user says that 2 minute old data is always reliable and 1 minute is sometimes reliable. We're going to try it out and hope it is enough for our needs.
Used Quest software and it seemed to be a good monitoring solution. Here is a link.
http://www.quest.com/application-performance-monitoring-solutions/
Also performance monitoring of Windows may also help.
I have a large ASP.NET website on a hosted platform. It shares the machine with a lot of other applications. We do not have access to the machine itself (only an FTP account).
Our client is complaining that it is starting to perform rather badly, particularly around peak hours. I've run some remote measurements (using a JMeter-like tool) that tells me that, yes, it does indeed perform rather badly during peak hours. It doesn't tell me why though. The client is resisting a move to a dedicated server without some hard facts.
As I see it, what I need are hard data about the machine itself. Setting up a local performance test environment would be extremely time-consuming, and I have no way to estimate the server performance.
My question: is there a good way to collect (a lot) of performance measurements when I have limited access to the machine, and certainly no access to the performance monitor? Any code would have to run in the asp.net application itself, without screwing it up too much.
We had a similar problem with our asp.net application hosted on a shared server, which also started to perform badly during peak hours.
Although I don't know of an elegant solution to your question, this is what we did:
Talk to your host providers to see what additional information they can give you - it's in their best interest to keep their clients happy. Our host providers were able to give us some time with one of their network engineers who provided us with some decent CPU and memory utilization stats.
Take your own performance measurements by dumping information to either a log file (using log4net) and/or the database - for example, user sessions, search times, page hits, timing measurements around key functionality. From this information we were able to ascertain what our systems normal behavior was for a set number of automation tests.
Setup a local server (not necessarily same stats as hosted/production server) with your application loaded and give it a full load/performance/capacity testing (we used Red Gate's ANTS Profiler). The stats that you gather from that will give you and your client a good indication of how the system should behave under certain loads with a known environment. Yes, this can be time consuming but it will give you a great performance measuring tool so that you can catch/fix bottlenecks locally rather than on production.
Good luck.