platinumthinker

#!/usr/bin/env escript

-include_lib("kernel/include/inet.hrl").
-include_lib("kernel/include/inet_sctp.hrl").

main([Protocol, IP, Port, Len, Cnt]) ->
    bench(list_to_atom(Protocol), inet:parse_address(IP),
	  list_to_integer(Port), list_to_integer(Len), list_to_integer(Cnt));
main(_) ->
    io:format("invalid arguments~n~n"),

platinumthinker

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

platinumthinker

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

platinumthinker

1> l(dyntrace).
{module,dyntrace}
2> erlang:trace_pattern({'_','_','_'}, [{'_', [], [{return_trace}]}], [local]). %% For function_call info
3> erlang:trace_pattern({'_','_','_'}, [{'_', [], [{exception_trace}]}], [local]). %% For exception info

4> erlang:trace(all, true, [call,'receive', send, {tracer,dyntrace,[]}]). %% Trace function calls with dyntrace (i.e. LTTng) and messaging
26

5> erlang:now(). %% Or whatever function call you want to trace. See the traces coming in LTTng log.

platinumthinker

#include <math.h>
#include <algorithm>
#include <string>
#include <pmmintrin.h>
using namespace std;typedef float R;
#define _W 79
#define _H 39
#define EP 0.01f
#define OP operator
#define C const