Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Sent: Saturday, December 06, 2008 9:14 PM
To: Clayton, Paul D
Cc: [EMAIL PROTECTED]; dtrace-discuss@opensolaris.org
Subject: Re: [dtrace-discuss] Concurrent Disk Activity from "Solaris
Performance & Tools" Chap. 4.17.4
> that in my spreadsheet. The part of the graph that is confusing me still
> is the offset of the 'strategy' line from 0 (zero) time. What is
> involved in figuring out what that ~100us offset from 0 for a bunch of
> block addresses? Where would THAT time offset come from with the DTrace
> script?
Concurrent Disk Activity from "Solaris
Performance & Tools" Chap. 4.17.4
Keep in mind that the service times are *averages* over the interval.
The average for the data in his spreadsheet would be pretty nice but
would
obscure the two pretty bad times he saw...
Jim
---
Jim Mauro wrot
Keep in mind that the service times are *averages* over the interval.
The average for the data in his spreadsheet would be pretty nice but would
obscure the two pretty bad times he saw...
Jim
---
Jim Mauro wrote:
> Hey Paul - I should add that "iostat -xnz 1" is a great method
> for determine ho
Hey Paul - I should add that "iostat -xnz 1" is a great method
for determine how well the SAN is performance.
The asvc_t times are disk IO service times in milliseconds.
I usually start there to sanity check disk IO times...
Thanks,
/jim
Paul Clayton wrote:
> Hello..
>
> Due to growing performa
Paul Clayton wrote:
> Hello..
>
> Due to growing performance problems on numerous systems, I have been reading
> through a lot of information about DTrace and what it can find out about a
> system. It is a great tool, and while there is a learning curve to using it
> successfully, getting usefu
Hi Paul -
>
> One thing I have been puzzled with a lot this weekend is the information and
> plot in Figure 4.7. This section if I understand it correctly, offers the
> means to track the actual times from when an IO starts in the kernel to when
> it completes, implying the time to either read
