Messages in this thread | | | Subject | Re: MD-RAID: Use seq_putc() in three status functions? | From | SF Markus Elfring <> | Date | Mon, 17 Oct 2016 13:10:18 +0200 |
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>> * Is a string pointer often longer than a byte? >> > Always.
I have got doubts for this specific information.
> (Which up to now I thought was basic programming knowledge...)
By the way: Run time environments still exist where the size of a pointer can be also just one byte, don't they?
>> How many results would we like to clarify from various hardware >> and software combinations? >> > See above. At the moment _any_ test result from your side would do.
I imagine that another single result might not be representative. How many lessons from test statistics will usually be also relevant here?
>> How important are the mentioned functions for you within the Linux >> programming interface so far? >> > Not very. The interface is only used in a slow path, and the execution > time doesn't affect I/O performance in any way.
Thanks for another interesting information.
>>> Case in point: with your patch the x86_64 compiler generates nearly >>> identical code for driver/md/raid1.c, but with one instruction _more_ >>> after your patch has been applied. >> >> Which software versions and command parameters did you try out >> for this information (from an unspecified run time environment)? >> > # gcc --version > gcc (SUSE Linux) 4.8.5
Thanks for this detail.
* Did you choose any special optimisation settings for your quick check?
* Will any compilation results matter if "optimisation" would be switched off there?
> I'm still waiting from results from your side.
Would any other software developers or testers dare to add related information?
Regards, Markus
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