/Simple-Experiments

Simple Experiments.

Primary LanguageShell

Simple Experiment.

1. False sharing

Move read-write variables which are often written to by different threads onto their own cache line.

  • My PC architecture
* Socket 0:
+---------------------------------------------+ 
| +--------+ +--------+ +--------+ +--------+ |
| |  0 4   | |  1 5   | |  2 6   | |  3 7   | |
| +--------+ +--------+ +--------+ +--------+ |
| +--------+ +--------+ +--------+ +--------+ |
| |  32 kB | |  32 kB | |  32 kB | |  32 kB | |
| +--------+ +--------+ +--------+ +--------+ |
| +--------+ +--------+ +--------+ +--------+ |
| | 256 kB | | 256 kB | | 256 kB | | 256 kB | |
| +--------+ +--------+ +--------+ +--------+ |
| +-----------------------------------------+ |
| |                   8 MB                  | |
| +-----------------------------------------+ |
+---------------------------------------------+
  • Simple Experiment
    struct node { 
        int var_odd; 
        int var_even;
    }
+ thread count : 8, interation count : 500000000, without lock
+ odd number thread write to var_odd (in odd number core with affinity option)
+ even number thread write to var_even (in even number core with affinity option)
    
    default : 11.234876 seconds
    cl_v1   : 11.544897 seconds
    cl_v2   : 7.091140  seconds 

    default core affinity : 10.124900 seconds 
    cl_v1   core affinity : 10.067641 seconds
    cl_v2   core affinity : 6.832389  seconds

2. YCSB/Redis, YCSB/MongoDB

Redis, MongoDB expriment script.

  • Simple Experiment
+ PMU event monitoring

3. CloudSuite 3.0 basic experiment script

CloudSuite 3.0 basic experiment script.

  • Simple Experiment
+ PMU event monitoring

4. Memory access pattern

Memory accesss pattern test for THP.

  • Simple Experiment
    typedef struct node_test{
        struct in{
            int val;
        };
        char pad[PAGE_SIZE - sizeof(struct in)];
    }__attribute__((aligned(PAGE_SIZE))) node;
+ stride access pattern in 4K unit, 2M unit
+ random access pattern 

+ "__alloc_pages_nodemask" execution time by ftrace by script
+ overload record by perf script