From: Nirmoy Das <ndas@suse.de>
To: ferruh.yigit@intel.com
Cc: dev@dpdk.org
Subject: [dpdk-dev] KNI latency improvement
Date: Fri, 29 Dec 2017 15:27:03 +0100 [thread overview]
Message-ID: <0a4ff780-55fc-7c42-e3ab-b6b22a73cfbd@suse.de> (raw)
Hi Ferruh,
There is latency in the range of milliseconds when packets are passed
through KNI up to the IP stack. With CONFIG_RTE_KNI_PREEMPT_DEFAULT=n
its required sacrifice a cpu core. Do you have any suggestion to improve
latency without sacrificing a cpu?
What do you think about using cond_resched() instead of
schedule_timeout_interruptible(), in our test it helped to reduce
latency?
Index: dpdk-stable-16.11.1/lib/librte_eal/linuxapp/kni/kni_misc.c
===================================================================
--- dpdk/lib/librte_eal/linuxapp/kni/kni_misc.c
+++ dpdk/lib/librte_eal/linuxapp/kni/kni_misc.c
@@ -150,9 +150,8 @@ kni_thread_single(void *data)
}
up_read(&knet->kni_list_lock);
#ifdef RTE_KNI_PREEMPT_DEFAULT
- /* reschedule out for a while */
- schedule_timeout_interruptible(
- usecs_to_jiffies(KNI_KTHREAD_RESCHEDULE_INTERVAL));
+ /* reschedule out */
+ cond_resched();
#endif
}
Regards,
Nirmoy
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next reply other threads:[~2017-12-29 14:27 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-29 14:27 Nirmoy Das [this message]
2017-12-29 17:13 ` Stephen Hemminger
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