SPMI (System Performance Measurement Interface)

SPMI (System Performance Measurement Interface)

Post by Marc Missir » Sat, 11 Dec 1999 04:00:00


I am looking for an AIX version of Solaris' kstat family of calls,
to retrieve statistics for CPU idleness and virtual memory paging info.

My search has led me to libSpmi.a,  the AIX SPMI.

Some questions,  though:

1) You have to have read permission on /dev/mem to even
run SpmiInit().  And you have to be able to create the
file if it does not exist already.  Is there any other system call or
set of calls
available to the average non-root user?

2)  Is SPMI a red herring for me,  and is there a simpler supported way
of doing this?
I tend to make things way too complicated if left to my own devices.

Thanks for any info/advice on this.

Here is a small Solaris C++ program which retrieves the info I want:


int main()
    int rc;
    kstat_ctl_t *kstatControlStruct;
    ulong idle, rest, reads_and_writes, pages_in_and_out;

    // Initialize the kernel statistics library
    if ( !kstatControlStruct )
        cerr << strerror(errno) << endl;
        return 1;

    // determine the number of CPUs
    // and read kstat data for each one
    int ncpu = 0;
    kstat_t *ksp;
    for ( ksp=kstatControlStruct->kc_chain; ksp != NULL;
        if( strcmp( ksp->ks_module, "cpu_stat" ) == 0 )
            if (kstat_read( kstatControlStruct, ksp, NULL ) < 0 )
                cerr << strerror(errno) << endl;
                return 1;
            cpu_stat_t   *percpu = (cpu_stat_t *)ksp->ks_data;
            idle =        percpu->cpu_sysinfo.cpu[CPU_IDLE] +
            rest =        percpu->cpu_sysinfo.cpu[CPU_USER] +

            reads_and_writes =  percpu->cpu_sysinfo.bread +
            pages_in_and_out =  percpu->cpu_vminfo.pgpgin +
    cout << "Number of CPUs: " << ncpu << endl;
    cout << "idle: " << idle << endl;
    cout << "rest: " << rest << endl;
    cout << "reads_and_writes: " << reads_and_writes << endl;
    cout << "pages_in_and_out: " << pages_in_and_out << endl;

    // free resources associated with the kstat control
    // structure
    rc = kstat_close( kstatControlStruct);
    if ( rc )
        cerr << strerror(errno) << endl;
        return 1;

    return 0;



Thanks for any info!



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