[dpdk-dev] [PATCH] mem: warn if address hint is not respected

[Xueming(Steven) Li]

Hi Jonas,

Seems you are trying to use --base-virtaddr to resolve address conflicts 
in secondary, I'm wondering how this happened and how to avoid it:
1. what's your hugepage side? Hugepage mmap is size aligned, maybe 1G works?
2. is there more libs loaded in secondary process or memory usage before 
EAL init?
3. Since address allocated in one direction, I'm thinking to reserve a 
larger "hop" address space as MAP_ANONYMOUS, allocate hugepage, then release 
"hop". That essentially reserve an address space big enough for secondary,
and most important the hop size is easy to estimate than --base-virtaddr.

Thanks,
Xueming(Steven)

> -----Original Message-----
> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Jonas Pfefferle1
> Sent: Wednesday, November 8, 2017 7:52 PM
> To: Burakov, Anatoly <anatoly.burakov at intel.com>
> Cc: dev at dpdk.org; jianfeng.tan at intel.com; Thomas Monjalon
> <thomas at monjalon.net>
> Subject: Re: [dpdk-dev] [PATCH] mem: warn if address hint is not respected
> 
> "Burakov, Anatoly" <anatoly.burakov at intel.com> wrote on 11/07/2017
> 02:54:24
> PM:
> 
> > From: "Burakov, Anatoly" <anatoly.burakov at intel.com>
> > To: Thomas Monjalon <thomas at monjalon.net>
> > Cc: dev at dpdk.org, Jonas Pfefferle <jpf at zurich.ibm.com>,
> jianfeng.tan at intel.com
> > Date: 11/07/2017 02:54 PM
> > Subject: Re: [dpdk-dev] [PATCH] mem: warn if address hint is not
> respected
> >
> > On 06-Nov-17 8:26 PM, Thomas Monjalon wrote:
> > > 31/10/2017 10:08, Jonas Pfefferle:
> > >> Print a warning if the --base-virtaddr hint is not respected since
> > >> this might lead to problems when mapping memory in the secondary
> > >> process.
> > >>
> > >> Signed-off-by: Jonas Pfefferle <jpf at zurich.ibm.com>
> > >
> > > Anatoly, please review this patch.
> > > It does not seem to fix something, so it is candidate for 18.02.
> > >
> >
> > For some reason my Thunderbird ate the original email, so i'll reply
> > to this one.
> >
> > One nitpick would be that we're calling get_virtual_area many times
> > and it would probably be a good idea to make pagesize static and call
> > sysconf only once. Otherwise,
> 
> We should address this in a separate patch and introduce a pagesize
> function for everyone to use. sysconf is used like this all over the place.
> 
> >
> > Acked-by: Anatoly Burakov <anatoly.burakov at intel.com>
> >
> > --
> > Thanks,
> > Anatoly
> >