[dpdk-dev] [PATCH v1 2/2] Test cases for rte_memcmp functions

[Wang, Zhihong]

> -----Original Message-----
> From: Thomas Monjalon [mailto:thomas.monjalon at 6wind.com]
> Sent: Tuesday, January 3, 2017 4:41 AM
> To: Wang, Zhihong <zhihong.wang at intel.com>; Ravi Kerur
> <rkerur at gmail.com>
> Cc: dev at dpdk.org
> Subject: Re: [dpdk-dev] [PATCH v1 2/2] Test cases for rte_memcmp
> functions
> 
> 2016-06-07 11:09, Wang, Zhihong:
> > From: Ravi Kerur [mailto:rkerur at gmail.com]
> > > Zhilong, Thomas,
> > >
> > > If there is enough interest within DPDK community I can work on adding
> support
> > > for 'unaligned access' and 'test cases' for it. Please let me know either
> way.
> >
> > Hi Ravi,
> >
> > This rte_memcmp is proved with better performance than glibc's in aligned
> > cases, I think it has good value to DPDK lib.
> >
> > Though we don't have memcmp in critical pmd data path, it offers a better
> > choice for applications who do.
> 
> Re-thinking about this series, could it be some values to have a rte_memcmp
> implementation?

I think this series (rte_memcmp included) could help:

 1. Potentially better performance in hot paths.

 2. Agile for tuning.

 3. Avoid performance complications -- unusual but possible,
    like the glibc memset issue I met while working on vhost
    enqueue.

> What is the value compared to glibc one? Why not working on glibc?

As to working on glibc, wider design consideration and test
coverage might be needed, and we'll face different release
cycles, can we have the same agility? Also working with old
glibc could be a problem.