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From: Dipen Patel <dipenp@nvidia.com>
To: <linux-rt-users@vger.kernel.org>
Subject: Multi pthreaded RT application - mlock doubt
Date: Wed, 31 Mar 2021 19:06:26 -0700	[thread overview]
Message-ID: <896cf71c-f610-961a-9d30-8a82d433e0f6@nvidia.com> (raw)

Hi,

I was following https://rt.wiki.kernel.org/index.php/Threaded_RT-application_with_memory_locking_and_stack_handling_example with some below changes:

1. Added 8 threads
2. Moved show_new_pagefault_count logic inside thread function once thread starts running as below:

thread_fn {

	getrusage(RUSAGE_SELF, &usage);
	
	print and save usage.ruminflt;

	prove_thread_stack_use_is_safe

	getrusage(RUSAGE_SELF, &usage);

	print usage.ruminflt - last_saved_cnt;
}

I observed there are still page faults (although not in big numbers as if there was no mlock), after touching stack in prove_thread_stack_use_is_safe call. I played around with MY_STACK_SIZE (from 1KB to 1MB) but still see minor page faults.

I am running 4.9.201_rt134 kernel. Any idea what I will be missing?

Best Regards,
Dipen Patel

             reply	other threads:[~2021-04-01  2:02 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-01  2:06 Dipen Patel [this message]
2021-05-25  3:08 ` Multi pthreaded RT application - mlock doubt Dipen Patel
2021-05-25  7:26 ` Ahmed S. Darwish
2021-05-25 22:24   ` Dipen Patel
2021-05-26  8:31     ` Ahmed S. Darwish
2021-05-26 10:26       ` John Ogness

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