Re: Linux VFS cache hit rate script

[Jake Maul <jakemaul at gmail dot com>]

New version of the script uploaded to War Stories, incorporating your
suggested changes. I have no problem with the GPLv2, so I took your
wording exactly. :)

http://sourceware.org/systemtap/wiki/WSCacheHitRate

Of course there's still the concern about devname "N/A", but I
clarified the comment so as to make it obvious where I got that
assumption from. At least then if does turn out to be incorrect, it
will be obvious that something other than just this one script needs
to be fixed.

Jake


On Wed, Apr 20, 2011 at 1:08 PM, William Cohen <wcohen@redhat.com> wrote:
> On 04/20/2011 03:04 PM, Jake Maul wrote:
>> Greetings all,
>
> Hi Jake,
>
> Thanks for taking the time to submit the example.
>
>>
>> I have recently put a script up on the War Stories page, and it was
>> requested of me to also post it to the list, along with a .meta file.
>> They're both attached.
>>
>> http://sourceware.org/systemtap/wiki/WSCacheHitRate
>
> Why the need for ?-DMAXMAPENTRIES=100000 on the second example on the wiki page? There doesn't seem to be any arrays in the script.
>
>>
>> Let me know what you think! It's my first SystemTap script, so I'm
>> sure there are improvements that could be made. I'm by no means a
>> kernel hacker, or even a C dev... just a lowly sysadmin. :)
>
> Include a short header like the following at the beginning of the script:
>
> #!/usr/bin/env stap
> # cache-hit.stp
> # Copyright (C) 2011 xxx <xxx@yyy.zzz>
> #
> # This program is free software; you can redistribute it and/or modify
> # it under the terms of the GNU General Public License version 2 as
> # published by the Free Software Foundation.
>
>
> Should avoid long line lengths in the printf statements. Wrapped lines don't look good in manuals.
>
>
> The following line sounds unsure, need to check that that is really the case:
>
> ?if (devname=="N/A") { /* N/A means cache hit... right? */
>
> It would be good to have a better explanation for the "N/A" check.
>
> -Will
>
>