I have a website that need a database to store some user information and a blob storage to save some files.
I want to minimize the cost as much as possible so I played around in Microsoft Azure Pricing Calculator with a Azure SQL Database. For the database I think that over it's hole lifetime 2GB of storage would be enought.
I arrived to 2 options that where dirt cheap but I don't really understand what it gives me.
First is with a serverles computer for 3600 seconds (of runtime?)
Is that time the time that my database is processing the request? For example if I have a select statement that takes 1 sec to complete I'll be left with 3599 sec for that month?
If that's the case what happens if I run out of time?
Second option is using a Hardware Type: Gen 4
but for this one I don't have any other options to configure my needs. Is this obsolete? Can I rely on it for production?
If you need a very cheap one use the Basic or S0.
Keep in mind that Basic are very slow: try to connect to it through SSMS.
Serverless is for databases that you pause for 3/4 of the day. It might be the case for you but keep in mind that when you use them they will cost a lot. I don't think this will be suitable for you.
I have a redis server running and I wanted to use JMeter to get the benchmarks and to find in how much time it hits 20K transactions per second. I have a hash setup. How should I go about querying it. I have put one of the keys as redis key and have put one of the fields of the hash as variable name.
If I use constant throughput timer, what should I enter in the name field.
Thanks in advance.
If you're planning to use Constant Throughput Timer and your target it to get 20k requests per second load you need to configure it as follows:
Target Throughput: 1200000 (20k per second * 60 seconds in minute)
Calculate Throughput based on: all active threads
See How to use JMeter's Throughput Constant Timer article for more details.
Few more recommendations:
Constant Throughput Timer can only pause the threads so make sure you have enough virtual users on Thread Group level
Constant Throughput Timer is accurate enough on "minute" level, so make sure your test lasts long enough so the timer will be correctly applied. Also consider reasonable ramp-up period.
Some people find Throughput Shaping Timer easier to use
20k+ concurrent threads is normally something you cannot achieve using single machine so it is likely you'll need to consider Distributed Testing when multiple JMeter instances act as a cluster.
I am trying to find an applications scalibility point using JMeter. I define the scalability point as "The minimum number of concurrent users from which any increase no longer increases the Throughput per second".
I am using the following technique. Schedule my load test to run for an hour, starting a new thread sending SOAP/XML-RPC Requests every 30 seconds. I do this by setting my number of threads to 120 and my ramp up period to 3600 seconds.
Then looking at my TOTAL rows Throughput in my Summary Report Listener. A new row (thread) is added every 30 seconds, the total throughput number rises until it plateaus at about 123 requests per second after 80 of the threads are active in my case. It then slowly drops the throughput number to 120 per second as the last 20 threads are added. I then conclude that my applications scalability point is 123 requests per second with 80 active users.
My question, is this a valid way to find an application scalibility point or is there different technique that I should be trying?
From a technical perspective what you're doing does answer your question regarding one specific user scenario, though I think you might be missing the big picture.
First of all keep in mind that the actual HTTP request you're sending and ramp up times can often impact what you call a scalability point. Are your requests hitting a cache? Are they not random enough? Are they too random? Do they represent real world requests? is 30 seconds going to give you the same results as 20 seconds or 10 seconds?
From my personal experience it's MUCH easier and more intuitive to look at graphs when trying to analyze app performance. It's not just a question of raw numbers but also looking and trends and rates of change.
For example here is an example testing the ghost.org blogging platofom using JMeter with an interactive JMeter results graph.
http://blazemeter.com/blog/ghost-performance-benchmark
This is what we have know:
web server in the UK + SQL SERVER in the UK
Because we can't make live replication of the database we come up this solution for the US:
web server in the US + talk with the SQL SERVER in the UK.
And we see a strange result, we got a slow connection of the page, it's more slow from making proxy from the US to the UK and we don't understand why.
The logic said to us that the sql data is smaller then the proxy (of all the data in the page).
Do you have any ideas?
If you want your SQL database to be that far away from your server, you need to seriously think about reducing the number of sequential queries used.
If your round-trip ping is 0.2ms to the MySQL server, and you make a query, this waits for round-trip communication. If you make 5 round-trip queries sequentially (that is, you wait for the first query to end before starting the second), it will take 0.2ms * 5 = 1ms.
Adding 1ms extra latency is no big deal. You probably won't notice.
If your database server is located outside the same datacenter, you'll probably get at least 20ms latency to the database. Five queries in a row would then take 100ms. Still not that bad.
If you're located across the ocean from your datacenter, you're probably talking 100-200ms latency. Five sequential queries would then take as long as a full second to return.
If you use 20-30 queries throughout the backend, it could take 10+ seconds to load your page.
Solutions?
Put your database server in the same datacenter as your web server. Unless you can do all queries in parallel, or reduce the system to a single query per page, it's actually faster to have your webserver in the UK than to separate the web server and database server by an ocean.
Greatly reduce the number of queries.
Cache.
I have no frame of reference in terms of what's considered "fast"; I'd always wondered this but have never found a straight answer...
OpenStreetMap seems to have 10-20 per second
Wikipedia seems to be 30000 to 70000 per second spread over 300 servers (100 to 200 requests per second per machine, most of which is caches)
Geograph is getting 7000 images per week (1 upload per 95 seconds)
Not sure anyone is still interested, but this information was posted about Twitter (and here too):
The Stats
Over 350,000 users. The actual numbers are as always, very super super top secret.
600 requests per second.
Average 200-300 connections per second. Spiking to 800 connections per second.
MySQL handled 2,400 requests per second.
180 Rails instances. Uses Mongrel as the "web" server.
1 MySQL Server (one big 8 core box) and 1 slave. Slave is read only for statistics and reporting.
30+ processes for handling odd jobs.
8 Sun X4100s.
Process a request in 200 milliseconds in Rails.
Average time spent in the database is 50-100 milliseconds.
Over 16 GB of memcached.
When I go to the control panel of my webhost, open up phpMyAdmin, and click on "Show MySQL runtime information", I get:
This MySQL server has been running for 53 days, 15 hours, 28 minutes and 53 seconds. It started up on Oct 24, 2008 at 04:03 AM.
Query statistics: Since its startup, 3,444,378,344 queries have been sent to the server.
Total 3,444 M
per hour 2.68 M
per minute 44.59 k
per second 743.13
That's an average of 743 mySQL queries every single second for the past 53 days!
I don't know about you, but to me that's fast! Very fast!!
personally, I like both analysis done every time....requests/second and average time/request and love seeing the max request time as well on top of that. it is easy to flip if you have 61 requests/second, you can then just flip it to 1000ms / 61 requests.
To answer your question, we have been doing a huge load test ourselves and find it ranges on various amazon hardware we use(best value was the 32 bit medium cpu when it came down to $$ / event / second) and our requests / seconds ranged from 29 requests / second / node up to 150 requests/second/node.
Giving better hardware of course gives better results but not the best ROI. Anyways, this post was great as I was looking for some parallels to see if my numbers where in the ballpark and shared mine as well in case someone else is looking. Mine is purely loaded as high as I can go.
NOTE: thanks to requests/second analysis(not ms/request) we found a major linux issue that we are trying to resolve where linux(we tested a server in C and java) freezes all the calls into socket libraries when under too much load which seems very odd. The full post can be found here actually....
http://ubuntuforums.org/showthread.php?p=11202389
We are still trying to resolve that as it gives us a huge performance boost in that our test goes from 2 minutes 42 seconds to 1 minute 35 seconds when this is fixed so we see a 33% performancce improvement....not to mention, the worse the DoS attack is the longer these pauses are so that all cpus drop to zero and stop processing...in my opinion server processing should continue in the face of a DoS but for some reason, it freezes up every once in a while during the Dos sometimes up to 30 seconds!!!
ADDITION: We found out it was actually a jdk race condition bug....hard to isolate on big clusters but when we ran 1 server 1 data node but 10 of those, we could reproduce it every time then and just looked at the server/datanode it occurred on. Switching the jdk to an earlier release fixed the issue. We were on jdk1.6.0_26 I believe.
That is a very open apples-to-oranges type of question.
You are asking
1. the average request load for a production application
2. what is considered fast
These don't neccessarily relate.
Your average # of requests per second is determined by
a. the number of simultaneous users
b. the average number of page requests they make per second
c. the number of additional requests (i.e. ajax calls, etc)
As to what is considered fast.. do you mean how few requests a site can take? Or if a piece of hardware is considered fast if it can process xyz # of requests per second?
Note that hit-rate graphs will be sinusoidal patterns with 'peak hours' maybe 2x or 3x the rate that you get while users are sleeping. (Can be useful when you're scheduling the daily batch-processing stuff to happen on servers)
You can see the effect even on 'international' (multilingual, localised) sites like wikipedia
less than 2 seconds per user usually - ie users that see slower responses than this think the system is slow.
Now you tell me how many users you have connected.
You can search "slashdot effect analysis" for graphs of what you would see if some aspect of the site suddenly became popular in the news, e.g. this graph on wiki.
Web-applications that survive tend to be the ones which can generate static pages instead of putting every request through a processing language.
There was an excellent video (I think it might have been on ted.com? I think it might have been by flickr web team? Does someone know the link?) with ideas on how to scale websites beyond the single server, e.g. how to allocate connections amongst the mix of read-only and read-write servers to get best effect for various types of users.
I have a customer that uses our software on a commercial web app servers. The software runs on 40 servers. The software is a 10 year old Java API.
4000 TPS.