dtrace discuss - Nov 2008 - Formatting quantize data for easy parsing

When printa() prints quantize data, you get the nice ascii art by default.

Can you change the format so that it''s all on one line and easier to
parse?
-- 
This message posted from opensolaris.org

On Tue, Nov 18, 2008 at 06:55:09AM -0800, Adam Mitchell
wrote:
> When printa() prints quantize data, you get the nice ascii art by default.
> Can you change the format so that it''s all on one line and easier
to parse?
Hey Adam,

There isn''t a way to format the results of a quantize action. The
closest
think I can think of is to change use the count() aggregating action keyed
by what would have been the argument to quantize:

---8<---

#!/usr/sbin/dtrace -s

#pragma D option aggsortkey

syscall::write:entry
{
        this->a = arg2;
        this->k = (this->a == 0) ? 0 : 1;

        this->k += (this->a & 0xffffffff00000000ULL) ? 32 : 0;
        this->a = (this->a & 0xffffffff00000000ULL) ? (this->a
>> 32) : this->a;
        this->k += (this->a & 0xffff0000) ? 16 : 0;
        this->a = (this->a & 0xffff0000) ? (this->a >> 16) :
this->a;
        this->k += (this->a & 0xff00) ? 8 : 0;
        this->a = (this->a & 0xff00) ? (this->a >> 8) :
this->a;
        this->k += (this->a & 0xf0) ? 4 : 0;
        this->a = (this->a & 0xf0) ? (this->a >> 4) :
this->a;
        this->k += (this->a & 0xc) ? 2 : 0;
        this->a = (this->a & 0xc) ? (this->a >> 2) :
this->a;
        this->k += (this->a & 0x2) ? 1 : 0;
        this->a = (this->a & 0x2) ? (this->a >> 1) :
this->a;

        @a[this->k] = count();
        @b = quantize(arg2);
}

---8<---

Adam

-- 
Adam Leventhal, Fishworks                     http://blogs.sun.com/ahl