zfs-dmu-delay-by-spa.d

#!/usr/sbin/dtrace -Cs
#pragma D option quiet
#define NSECS_IN_MSEC 1000000

:zfs:dmu_tx_wait:entry {
    self->in = timestamp;
    self->spa = (string)((char *)args[0]->tx_pool->dp_spa->spa_name);
}
:zfs:dmu_tx_wait:return /self->in/ {
    this->delta = timestamp - self->in;
    @q[self->spa] = quantize(this->delta);
    @max_delay[self->spa] = max(this->delta);
    self->in = 0; self->spa = 0;
}
tick-5sec {
    normalize(@max_delay, NSECS_IN_MSEC); /* convert nano to milliseconds */
    printa("\t(%s) max delay: %@d(mS)%@d\n", @max_delay, @q);
    trunc(@q); trunc(@max_delay);
}