Messages in this thread | | | Date | Tue, 6 Dec 2022 10:35:07 +0800 (CST) | From | <> | Subject | Re: [PATCH linux-next] net: record times of netdev budget exhausted |
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On Tue, 6 Dec 2022 09:53:05 +0800 (CST) kuba@kernel.org wrote: > time_squeeze is extremely noisy and annoyingly useless, > we need to understand exactly what you're doing before > we accept any changes to this core piece of code.
The author of "Replace 2 jiffies with sysctl netdev_budget_usecs to enable softirq tuning" is Matthew Whitehead, he said this in git log: Constants used for tuning are generally a bad idea, especially as hardware changes over time...For example, a very fast machine might tune this to 1000 microseconds, while my regression testing 486DX-25 needs it to be 4000 microseconds on a nearly idle network to prevent time_squeeze from being incremented.
And on my systems there are huge packets on the intranet, and we came accross with lots of time_squeeze. The idea is that, netdev_budget* are selections between throughput and real-time. If we care throughput and not care real-time so much, we may want bigger netdev_budget*.
In this scenario, we want to tune netdev_budget* and see their effect separately.
By the way, if netdev_budget* are useless, should they be deleted?
Thanks.
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