gistfile1.txt

#!/usr/sbin/dtrace -qs

#pragma D option aggsize=8m
#pragma D option bufsize=8m
#pragma D option dynvarsize=8m

inline int BIO_READ=0x01;
inline int BIO_WRITE=0x02;
inline int BIO_DONE=0x02;

fbt::zfs_freebsd_read:entry
{
	@zr["ZFS READ"] = quantize(args[0]->a_uio->uio_resid);
}

fbt::zfs_freebsd_write:entry
{
	@zw["ZFS WRITE"] = quantize(args[0]->a_uio->uio_resid);
}

io:::start
/arg0 && args[0]->bio_cmd & BIO_READ/
{
	@vr["DSK READ"] = quantize(args[0]->bio_bcount);
}

io:::start
/arg0 && args[0]->bio_cmd & BIO_WRITE/
{
	@vw["DSK WRITE"] = quantize(args[0]->bio_bcount);
}

tick-5s
{
	printf("\nTIME %d %Y\n", walltimestamp / 1000000000, walltimestamp);
	printa(@zr);
	printa(@zw);
	printa(@vr);
	printa(@vw);
	trunc(@zr);
	trunc(@zw);
	trunc(@vr);
	trunc(@vw);
}