don’t use jMeter to test Apache!

rephrase… “do not use jMeter to test very fast response time applications”

about httpclient: But why isn’t the problem deterministic? Shouldn’t it never recover once the problem starts to happen? The magic is Java garbage collection. I reproduced the effect by forcing garbage collection. It will clean CLOSE_WAIT connections. But, to be accurate, JVM garbage collection does not handle socket closing by itself. It only frees memory. It is Socket object who closes sockets in finanize method as discussed here.

CLOSE_WAIT socket state, Socket object, finalize & garbage collection

you end up with having garbage collection slowdowns on client side (one more link), and that will effect your metrics collection as well… no matter how high you tune your ulimit(this limits how many sockets your process can concurrently open)… you simply can’t test a such an application with a jMeter… it is “too slow” …grinder is a bad choice as well (everything Java based!)

if you want to do so, good will be “ab” aka Apache Benchmark, with the limitations to the scenario you can describe… it won’t allow you do to complex load and performance testing scenarios… it is basically hitting ONLY one url… but it can help when you need to stress a specific call, or your apache settings

other good choice might be tSung, written in Erlang… the system creates queues of tasks, and you can simulate a pretty heavy amount of “browser like scenarios”, having multiple parallel request just after the html has been retrieved… to get js, css, and images…

(4 italians only: “ditelo a Brunetta! – il Fatto Quotidiano: Certificati medici online, sistemi in tilt“)

webservices? well… in 2 years and a half in Vodafone we came to the conclusion that grinder with our self made HTTP-QAT toolkit was the best choice… (create your request from the WSDL with SoapUI and then put it in as a template inside HTTP-QAT, and fire!!!! :p )

I’d like to spend time to integrate tools like cucumber and tSung
performance and easy way to describe/document the test scenario

Also Hadoop, with JFreeChart would be a good rewrite of Ground Report

what’s “ab”?
(read below, 95% of my requests were pretty fast…
we have some long tails on 5% of the overall sent http calls… )

grinder:~ zeph$ ab -c 5 -n 100 http://localhost/ This is ApacheBench, Version 2.3 Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/ Licensed to The Apache Software Foundation, http://www.apache.org/ Benchmarking localhost (be patient).....done Server Software: Apache/2.2.15 Server Hostname: localhost Server Port: 80 Document Path: / Document Length: 44 bytes Concurrency Level: 5 Time taken for tests: 0.570 seconds Complete requests: 100 Failed requests: 0 Write errors: 0 Total transferred: 42500 bytes HTML transferred: 4400 bytes Requests per second: 175.45 [#/sec] (mean) Time per request: 28.498 [ms] (mean) Time per request: 5.700 [ms] (mean, across all concurrent requests) Transfer rate: 72.82 [Kbytes/sec] received Connection Times (ms) min mean[+/-sd] median max Connect: 0 0 0.2 0 1 Processing: 0 15 80.6 1 569 Waiting: 0 15 80.6 1 569 Total: 1 15 80.7 1 570 Percentage of the requests served within a certain time (ms) 50% 1 66% 1 75% 1 80% 2 90% 2 95% 78 98% 569 99% 570 100% 570 (longest request)

Nokia & Microsoft

non hanno ancora bussato alla mia porta, non mi sono (per fortuna!) ancora venuti a dire: “tu da domattina ci supporti server .NET” … continuo a gestire Linux su 6 datacenter in 4 continenti, continuo a fare il lavoro per cui ho scelto di lavorare in Nokia

questo e’ quello che ho provato stamane:

Grief and disbelief greet Elop’s Nokia revolution

sapro’ maggiori dettagli nei prossimi giorni… per ora questo post, voglio raccogliere le vostre di impressioni (ho gia’ avuto qualcuno che mi ha scritto in privato, oltre ai post sull wall di Facebook)

…quoto questa ad esempio:

Dear Stephen Elop,
I’m a life long Nokia customer (7-8 phones in my family) currently
owning an X6 and an Ovi Store developer with an almost ready Qt
application.
I think you are dooming Nokia to bankruptcy.
It seems that you’re dumping all the core software assets of Nokia:
Symbian, Qt, expertize in Linux and many others.
Personally I was planning to buy in few months an N9 for me and a C7 for
my wife.
Now I will sell my X6 and buy two Android phones.
I heard of dozens of people like me planning to buy Nokia that now will
buy Android or Bada.
I repeat, I think you’re killing Nokia.

p.s. twittate… ogni giorno i vostri commenti riguardo a #nokia, #ovi, #ovimaps, vengono stampati e attaccati in giro per l’azienda… sia quelli positivi, ma soprattutto quelli negativi… fatevi sentire!

impegnato o?

o non ho piu’ un cacchio da dire? sinceramente, preferisco non dire piu’ nulla, politicamente parlando, dopo quello che e’ accaduto a Dicembre… sono deluso / amareggiato / incazzato / ammutolito / frastornato / rassegnato

mi sto dedicando al lavoro, mi diverto come un cretino, le nuove sfide sono entusiasmanti… chissa’ che non riesca a dare un apporto significativo

beh, un abbraccio a tutti gli amici… Buon Anno! 🙂