Modifying Samba to skip file system reads for IOZONE READ and
rsharpe at richardsharpe.com
Fri Oct 28 23:57:57 GMT 2005
On Fri, 28 Oct 2005, Iozone wrote:
>>> The new version of Iozone will become available within the
>>> next 24 hours on the Iozone web site. This version will
>>> disable your, un-ethical, hack. Please take a few moments
>>> of introspection and ponder of the value of honesty to
>>> the public. There is no real value in providing mechanisms
>>> that tell lies to the consumer.
>> Can you explain more about this post ? I don't think I've understood
>> what has been going on here ?
>> Jeremy Allison,
>> Samba Team.
> Iozone measures a filesystem's performance by writing and
> reading files. Mr. Sharpe, provided a hack in Samba that
> detects when Iozone is running. (keying off of the file names
> that Iozone uses) This hack intercepts the user's reading
> of a file, detects that it is Iozone running, and then
> allocates buffers and fills them in with what it knows
> Iozone wants. Thus, the user's reads NEVER made it
> to the filesystem at all, and the results reported by
> Iozone will not reflect the filesystem, but a deliberate
> HACK, specifically targeted towards circumventing
> accurate measurement by Iozone. Thus, telling the user
> lies. These lies will NOT reflect any other application
> running and will only mislead the consumer into believing
> that the system is fast, when in reality it may suck big-time !
> Richard's code is NOT cool. It is a deliberate attempt
> to tell the users of Samba LIES. IT IS NOT COOL !
> I have immediately modified Iozone so that Richard's
> hack will not work, and in fact, will now only serve to
> demonstrate that Samba is broken, and returning the
> WRONG data from a file that was just written.
> Iozone will change the contents of its data files with every
> new version. Any attempt to try this sort of *&&%&% again
> will result in Iozone telling the user that Samba is broken
> and should not be used for storing data.
> Richard: Your hack is NOT in the interest of honesty
> or beneficial to the public. It is just plain evil.
I have always found your help in the past to be very useful, but I fear
you have over-reacted to something that was intended to help people debug
I have already responded to an earlier message, and did so before seeing
this response. However, I feel that I must respond.
Did you think about what you were typing before making claims that I am an
Perhaps if you had sent me a short email asking me what my intent was
before making outrageous public claims we could have dealt with the issue
in a more reasonable manner.
For the record, I agree that people should not be able to defeat
benchmarking programs like IOZONE and so forth.
Richard Sharpe, rsharpe[at]richardsharpe.com, rsharpe[at]samba.org,
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