Currently working on the performance of my RESTFul api implemented using node js and mysql. For load testing of my APIs I'm using jmeter. So When I call my one of url for testing load with configuration
Virtual Users : 100,
Total Duration : 60s,
Time delay : 0s,
Ramup-Period : 1s
Jmeter show status OK for around 300-400 results and after that It timeouts for rest of request. Then after this I'm not able to ssh login or ping my server from my system till restart my system. Why this is happening?. Is it problem of my APIs design or server load problems.
Most probably your server simply becomes overloaded, I would suggest monitoring its baseline health metrics using top, vmstat, sar etc during your test execution. Also consider increasing your ramp-up period setting so load would increase more gradually - this way you will be able to correlate system behavior with the increasing load and determine what is the maximum of concurrent requests your system is able to serve.
Alternatively (or in addition to top, vmstat and sar) you can use JMeter PerfMon Plugin which is capable of collecting a lot of metrics and sending them to JMeter so you will have system performance report along with the load test results. Check out How to Monitor Your Server Health & Performance During a JMeter Load Test guide for detailed installation and configuration instructions along with usage examples.
Related
I'm currently in the first phase of optimizing a gaming back-end. I'm using .NET Core 2.0, EF and MySQL. Currently all of this is running on a local machine, used for dev. To do initial load testing, I've written a small console app that simulates the way the final client will use the API. The API is hosted under IIS 8.5 on a Windows Server 2012R2 machine. The simulating app is run on 1-2 separate machines.
So, this all works very well for around 100-120 requests/s. The CPU load is around 15-30 on the server, the number of connections on the MySQL server averaging around 100 (I've set the max_connections to 400, and it's never near that value). Response times are averaging way below 100ms. However, as soon as we enter request figures a bit higher than that, it seems the system completely stalls on intervals. The CPU load drops to < 5, and the response times in the same time skyrockets. So, it kind of acts like a traffic jam situation. During the stall, both the MySQL and the dotnet exe's seem to "rest".
I do realize I'm no where near a production setup on anything, the MySQL instance is in dev etc. However, I'm still curious what would be the cause of this. Any ideas?
I have been using Google Cloud for quite some time and everything works fine. I was using single VM Instance to host both website and MySQL Database.
Recently, i decided to move the website to autoscale so that on days when the traffic increases, the website doesn't go down.
So, i moved the database to Cloud SQL and create a VM Group which will host the PHP, HTML, Image files. Then, i set up a load balancer to divert traffic to various VM Instances under VM Group.
The problem is that the Backend Service (VM Group inside load balancer) becomes unhealthy on its own after working fine for 5-6 hours and then again becomes healthy after 10-15 minutes. I have also seen that the problem can come when i run a file which is a bit lengthy with many MySQL Queries.
I checked the Health check and it was giving 200 response. During the down period of 10-15 minutes, the VM Instance is accessible from it own ip address.
Everything is same, i have just added a load balancer in front of the VM Instance and the problem has started.
Can anybody help me troubleshoot this problem?
It sounds like your server is timing out (blocking?) on the health check during the times the load balancer reports it as down. A few things you can check:
The logs (I'm presuming you're using Apache?) should include a duration along with the request status in the logs. The default health check timeout is 5s, so if your health check is returning a 200 in 6s, the health checker will time out after 5s and treat the host as down.
You mention that a heavy mysql load can cause the problem. Have you looked at disk I/O statistics and CPU to make sure that this isn't a load-related problem? If this is CPU or load related, you might look at increasing either CPU or disk size, or moving your disk from spindle-backed to SSD-backed storage.
Have you checked that you have sufficient threads available? Ideally, your health check would run fairly quickly, but it might be delayed (for example) if you have 3 threads and all three are busy running some other PHP script that's waiting on the database
I have an application hosted in openshift. Now I want figure out how many request can handle in order to check the speed and availability.
So my first attempt will be generate a multiple HTTP GET requests to my Rest Service(made in python and hosted in openshift).
My fear is can get my IP workplace banned regarding this looks like an attack.
In the other hand I see there are tools like New Relic or DataDog to check metrics, but I don't know if I can simulate http requests and then check the response times.
Openshift Response
I finally wrote to Openshift support and they told me I can simulate http requests without worries.
I recall the default behavior being that each gear can handle 16 concurrent connections, then auto-scaling would kick in and you would get a new gear. Therefore I would think it makes sense to start by testing that a gear works well with 16 users at once. If not, then you can change the scaling policy to what works best for you application.
BlazeMeter is a tool that could probably help with creating the connections. They mention 100,000 concurrent users on that main page so I don't think you have to worry about getting banned for this sort of test.
The situation is that about 50.000 electronic devices are going to connect to a webservice created in node.js once per minute. Each one is going to send a POST request containg some JSON data.
All this data should be secured.
The web service is going to receive those requests, saving the data to a database.
Also reading requests are possible to get some data from the DB.
I think to build up a system based on the following infrastructure:
Node.js + memcached + (mysql cluster OR Couchbase)
So, what memory requirements do I need to assign to my web server to be able to handle all this connections? Suppose that in the pessimistic possibility I would have 50.000 concurrent requests.
And what if I use SSL to secure the connections? Do I add too much overhead per connection?
Should I scale the system to handle them?
What do you suggest me?
Many thanks in advance!
Of course, it is impossible to provide any valuable calculations, since it is always very specific. I would recommend you just to develop scalable and expandable system architecture from the very beginning. And use JMeter https://jmeter.apache.org/ for load testing. Then you will be able to scale from 1000s to unlimited connections.
Here is a 1 000 000 connections article http://www.slideshare.net/sh1mmer/a-million-connections-and-beyond-nodejs-at-scale
Remember that your nodejs application will be single threaded. Meaning your performance will degrade horribly when you increase the number of concurrent requests.
What you can do to increase your performance is create a node process for each core that you have on your machine all of them behind a proxy (say nginx), and you can also use multiple machines for your app.
If you make requests only to memcache then your api won't degrade. But once you start querying mysql it will start throttling your other requests.
Edit:
As suggested in the comments you could also use clusters to fork worker processes and let them compete amongst each other for incoming requests. (Workers will run on a separate thread, thereby allowing you to use all cores).
Node.js on multi-core machines
I'm having trouble with a web service deployed on Tomcat. During peak traffic times the server is becoming non response and forces me to restart the entire server in order to get it working again.
First of all, I'm pretty new to all this. I built the server myself using various guides and blogs. Everything has been working great, but due to the larger load of traffic, I'm now getting out of my league a little. So, I need clear instructions on what to do or to be pointed towards exactly what I need to read up on.
I'm currently monitoring the service using JavaMelody, so I can see the spikes occurring, but I am unaware how to get more detailed information than this as to possible causes/solutions.
The server itself is quad core with 16gb ram, so the issue doesn't lie there, more likely in the fact I need to properly configure Tomcat to be able to use this (or setup a cluster...?)
JavaMelody shows the service crashing when the cpu usage only gets to about 20%, and about 300 hits a minute. Is there any max connection limits of memory settings that I should be configuring?
I also only have a single instance of the service deployed. I understand I can simply rename the war file and Tomcat deploys a second instance. Will doing this help?
Each request also opens (and immediately closes) a connection to mySQL to retrieve data, I probably need to be sure it's not getting throttled there too.
Sorry this is so long winded and has multiple questions. I can give more information as needed, I am just not certain what needs to be given at this time!
The server has 16Gs of ram but how much memory do you have dedicated to tomcat, -Xms and -Xmx?