High-Performance Timer vs StopWatch
Stopwatch is based on High resolution timer (where available), you can check that with IsHighResolution
benchmarking
POST request with wrk?
This is possible now. Here is an example https://github.com/wg/wrk/blob/master/scripts/post.lua. wrk.method = “POST” wrk.body = “foo=bar&baz=quux” wrk.headers[“Content-Type”] = “application/x-www-form-urlencoded” save this in a *.lua script and pass it into your command line test with the -s flag.
What does “an intermediate result is being cached” mean?
The message “intermediate result is being cached” is just a blind guess in the canned message reported by %timeit. It may or may not be true, and you should not assume it is correct. In particular, one of the most common reasons for the first run being slowest is that the array is in the … Read more
How to test only one benchmark function?
Description of testing flags -test.bench pattern Run benchmarks matching the regular expression. By default, no benchmarks run. -test.run pattern Run only those tests and examples matching the regular expression. For convenience, each of these -test.X flags of the test binary is also available as the flag -X in ‘go test‘ itself. For help, $ go … Read more
How do you time a function in Go and return its runtime in milliseconds?
Go’s defer makes this trivial. In Go 1.x, define the following functions: func trace(s string) (string, time.Time) { log.Println(“START:”, s) return s, time.Now() } func un(s string, startTime time.Time) { endTime := time.Now() log.Println(” END:”, s, “ElapsedTime in seconds:”, endTime.Sub(startTime)) } After that, you get Squeaky Clean one line elapsed time log messages: func someFunction() … Read more
Why is 2 * x * x faster than 2 * ( x * x ) in Python 3.x, for integers?
First of all, note that we don’t see the same thing in Python 2.x: >>> timeit(“for i in range(1000): 2*i*i”) 51.00784397125244 >>> timeit(“for i in range(1000): 2*(i*i)”) 50.48330092430115 So this leads us to believe that this is due to how integers changed in Python 3: specifically, Python 3 uses long (arbitrarily large integers) everywhere. For … Read more
How to benchmark functions in Clojure?
If it’s just a matter of wanting to capture the string programmatically, you can bind *out* to something else before using time. user=> (def x (with-out-str (time (+ 2 2)))) #’user/x user=> x “\”Elapsed time: 0.119 msecs\”\n” If you want more control over the format, then you can create your own version of time using … Read more
How to benchmark programs in Rust?
It might be worth noting two years later (to help any future Rust programmers who stumble on this page) that there are now tools to benchmark Rust code as a part of one’s test suite. (From the guide link below) Using the #[bench] attribute, one can use the standard Rust tooling to benchmark methods in … Read more
How am I supposed to interpret the results from Apache’s ab benchmarking tool?
Frustrating, isn’t it? I am trying to do the same thing, see how my newly provisioned and configured dedicated server compares to others. What I am ending up doing is comparing my current production server (Dual core 4GB RAM) to the new server (Quad core 8GB RAM). I need to ‘play nice’ with my side … Read more
Does Rust’s array bounds checking affect performance?
Unfortunately, the cost of a bounds check is not a straightforward thing to estimate. It’s certainly not “one cycle per check”, or any such easy to guess cost. It will have nonzero impact, but it might be insignificant. In theory, it would be possible to measure the cost of bounds checking on basic types like … Read more