* [dpdk-dev] igb PMD should set the default tx wthresh correctly.
@ 2015-07-16 17:16 Stephen Hemminger
2015-07-17 0:52 ` Lu, Wenzhuo
0 siblings, 1 reply; 6+ messages in thread
From: Stephen Hemminger @ 2015-07-16 17:16 UTC (permalink / raw)
To: Wenzhuo Lu; +Cc: dev
Why doesn't igb driver set the wthresh it wants as default?
I see:
PMD: eth_igb_tx_queue_setup(): To improve 1G driver performance, consider setting the TX WTHRESH value to 4, 8, or 16.
But the default tx_conf has wthresh of 0.
#define IGB_DEFAULT_TX_WTHRESH 0
Either message should be removed or default TX wthresh should change.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [dpdk-dev] igb PMD should set the default tx wthresh correctly.
2015-07-16 17:16 [dpdk-dev] igb PMD should set the default tx wthresh correctly Stephen Hemminger
@ 2015-07-17 0:52 ` Lu, Wenzhuo
2015-07-17 2:49 ` Stephen Hemminger
0 siblings, 1 reply; 6+ messages in thread
From: Lu, Wenzhuo @ 2015-07-17 0:52 UTC (permalink / raw)
To: Stephen Hemminger; +Cc: dev
Hi Stephen,
I don't think there's a conflict. The message just reminder us that we can adjust the values to achieve better performance.
I saw ixgbe and i40e also use 0 as the same default value. To my opinion, it's good to keep the same behavior.
Thanks.
> -----Original Message-----
> From: Stephen Hemminger [mailto:shemming@brocade.com]
> Sent: Friday, July 17, 2015 1:17 AM
> To: Lu, Wenzhuo
> Cc: dev@dpdk.org
> Subject: igb PMD should set the default tx wthresh correctly.
>
> Why doesn't igb driver set the wthresh it wants as default?
>
> I see:
> PMD: eth_igb_tx_queue_setup(): To improve 1G driver performance,
> consider setting the TX WTHRESH value to 4, 8, or 16.
>
> But the default tx_conf has wthresh of 0.
>
> #define IGB_DEFAULT_TX_WTHRESH 0
>
>
> Either message should be removed or default TX wthresh should change.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [dpdk-dev] igb PMD should set the default tx wthresh correctly.
2015-07-17 0:52 ` Lu, Wenzhuo
@ 2015-07-17 2:49 ` Stephen Hemminger
2015-07-17 8:15 ` Thomas Monjalon
0 siblings, 1 reply; 6+ messages in thread
From: Stephen Hemminger @ 2015-07-17 2:49 UTC (permalink / raw)
To: Lu, Wenzhuo; +Cc: dev
On Fri, 17 Jul 2015 00:52:09 +0000
"Lu, Wenzhuo" <wenzhuo.lu@intel.com> wrote:
> Hi Stephen,
> I don't think there's a conflict. The message just reminder us that we can adjust the values to achieve better performance.
> I saw ixgbe and i40e also use 0 as the same default value. To my opinion, it's good to keep the same behavior.
> Thanks.
In my opnion, no application should have to make special case setup
for each device type. Having to have a table that lists all the parameters
for each device name is not supportable or scaleable.
The DPDK started out as "lets do benchmarks fast" but as a production
toolkit it needs to stop having this kind of thing.
The message shows up to the end-user, who thinks it is a driver bug.
The "us" is now real customers not DPDK developers.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [dpdk-dev] igb PMD should set the default tx wthresh correctly.
2015-07-17 2:49 ` Stephen Hemminger
@ 2015-07-17 8:15 ` Thomas Monjalon
2015-07-17 11:06 ` Wiles, Keith
0 siblings, 1 reply; 6+ messages in thread
From: Thomas Monjalon @ 2015-07-17 8:15 UTC (permalink / raw)
To: Stephen Hemminger, Lu, Wenzhuo; +Cc: dev
2015-07-16 19:49, Stephen Hemminger:
> On Fri, 17 Jul 2015 00:52:09 +0000
> "Lu, Wenzhuo" <wenzhuo.lu@intel.com> wrote:
>
> > Hi Stephen,
> > I don't think there's a conflict. The message just reminder us that we can adjust the values to achieve better performance.
> > I saw ixgbe and i40e also use 0 as the same default value. To my opinion, it's good to keep the same behavior.
> > Thanks.
>
> In my opnion, no application should have to make special case setup
> for each device type. Having to have a table that lists all the parameters
> for each device name is not supportable or scaleable.
>
> The DPDK started out as "lets do benchmarks fast" but as a production
> toolkit it needs to stop having this kind of thing.
>
> The message shows up to the end-user, who thinks it is a driver bug.
> The "us" is now real customers not DPDK developers.
+1 to have better default values and less scary messages.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [dpdk-dev] igb PMD should set the default tx wthresh correctly.
2015-07-17 8:15 ` Thomas Monjalon
@ 2015-07-17 11:06 ` Wiles, Keith
2015-07-20 2:16 ` Lu, Wenzhuo
0 siblings, 1 reply; 6+ messages in thread
From: Wiles, Keith @ 2015-07-17 11:06 UTC (permalink / raw)
To: Thomas Monjalon, Stephen Hemminger, Lu, Wenzhuo; +Cc: dev
On 7/17/15, 9:15 AM, "dev on behalf of Thomas Monjalon"
<dev-bounces@dpdk.org on behalf of thomas.monjalon@6wind.com> wrote:
>2015-07-16 19:49, Stephen Hemminger:
>> On Fri, 17 Jul 2015 00:52:09 +0000
>> "Lu, Wenzhuo" <wenzhuo.lu@intel.com> wrote:
>>
>> > Hi Stephen,
>> > I don't think there's a conflict. The message just reminder us that
>>we can adjust the values to achieve better performance.
>> > I saw ixgbe and i40e also use 0 as the same default value. To my
>>opinion, it's good to keep the same behavior.
>> > Thanks.
>>
>> In my opnion, no application should have to make special case setup
>> for each device type. Having to have a table that lists all the
>>parameters
>> for each device name is not supportable or scaleable.
>>
>> The DPDK started out as "lets do benchmarks fast" but as a production
>> toolkit it needs to stop having this kind of thing.
>>
>> The message shows up to the end-user, who thinks it is a driver bug.
>> The "us" is now real customers not DPDK developers.
>
>+1 to have better default values and less scary messages.
+1 I agree we should have default values. The scary message is for
debugging only in the best of cases and just wrong for the normal case.
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [dpdk-dev] igb PMD should set the default tx wthresh correctly.
2015-07-17 11:06 ` Wiles, Keith
@ 2015-07-20 2:16 ` Lu, Wenzhuo
0 siblings, 0 replies; 6+ messages in thread
From: Lu, Wenzhuo @ 2015-07-20 2:16 UTC (permalink / raw)
To: Wiles, Keith, Thomas Monjalon, Stephen Hemminger; +Cc: dev
Hi,
> -----Original Message-----
> From: Wiles, Keith
> Sent: Friday, July 17, 2015 7:06 PM
> To: Thomas Monjalon; Stephen Hemminger; Lu, Wenzhuo
> Cc: dev@dpdk.org
> Subject: Re: [dpdk-dev] igb PMD should set the default tx wthresh correctly.
>
>
>
> On 7/17/15, 9:15 AM, "dev on behalf of Thomas Monjalon"
> <dev-bounces@dpdk.org on behalf of thomas.monjalon@6wind.com> wrote:
>
> >2015-07-16 19:49, Stephen Hemminger:
> >> On Fri, 17 Jul 2015 00:52:09 +0000
> >> "Lu, Wenzhuo" <wenzhuo.lu@intel.com> wrote:
> >>
> >> > Hi Stephen,
> >> > I don't think there's a conflict. The message just reminder us that
> >>we can adjust the values to achieve better performance.
> >> > I saw ixgbe and i40e also use 0 as the same default value. To my
> >>opinion, it's good to keep the same behavior.
> >> > Thanks.
> >>
> >> In my opnion, no application should have to make special case setup
> >>for each device type. Having to have a table that lists all the
> >>parameters for each device name is not supportable or scaleable.
> >>
> >> The DPDK started out as "lets do benchmarks fast" but as a production
> >> toolkit it needs to stop having this kind of thing.
> >>
> >> The message shows up to the end-user, who thinks it is a driver bug.
> >> The "us" is now real customers not DPDK developers.
> >
> >+1 to have better default values and less scary messages.
> +1 I agree we should have default values. The scary message is for
> debugging only in the best of cases and just wrong for the normal case.
After checking the code, igb and ixgbe/i40e's behavior is different for tx_rs_thresh
and tx wthresh, so now I think it's no necessary to let them have the same default value.
Agree that we shall remove the message or set an appropriate value for tx wthresh.
> >
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2015-07-20 2:16 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
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2015-07-16 17:16 [dpdk-dev] igb PMD should set the default tx wthresh correctly Stephen Hemminger
2015-07-17 0:52 ` Lu, Wenzhuo
2015-07-17 2:49 ` Stephen Hemminger
2015-07-17 8:15 ` Thomas Monjalon
2015-07-17 11:06 ` Wiles, Keith
2015-07-20 2:16 ` Lu, Wenzhuo
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